Définition acid | dictionnaire anglais définition synonymes Reverso

Collins

acid  


      n  
1    any substance that dissociates in water to yield a sour corrosive solution containing hydrogen ions, having a pH of less than 7, and turning litmus red  
   See also       Lewis acid  
2    a sour-tasting substance  
3       a slang name for       LSD  
      adj  
4      (Chem)  
a    of, derived from, or containing acid  
an acid radical     
b    being or having the properties of an acid  
sodium bicarbonate is an acid salt     
5    sharp or sour in taste  
6    cutting, sharp, or hurtful in speech, manner, etc.; vitriolic; caustic  
7    (of rain, snow, etc.) containing pollutant acids in solution  
8    (of igneous rocks) having a silica content of more than two thirds the total and containing at least one tenth quartz  
9      (Metallurgy)   of or made by a process in which the furnace or converter is lined with an acid material  
acid steel     
     (C17 (first used by Francis Bacon): from French acide or Latin acidus, from acere to be sour or sharp)  
  acidly      adv  
  acidness      n  
  acidy      adj  


abietic acid  
      n   a yellowish powder occurring naturally as a constituent of rosin and used in lacquers, varnishes, and soap. Formula: C19H29COOH; melting pt.: 173°C  
     (C19 abietic, from Latin abiet-, from abies silver fir (the acid originally being extracted from the resin))  
acetic acid  
      n   a colourless pungent liquid, miscible with water, widely used in the manufacture of acetic anhydride, vinyl acetate, plastics, pharmaceuticals, dyes, etc. Formula: CH3COOH,   (Systematic name)    ethanoic acid      See also       glacial acetic acid       vinegar  
acetylsalicylic acid  
      n      the chemical name for       aspirin  
acid anhydride  
      n      another name for       anhydride       3  
acid drop  
      n   a boiled sweet with a sharp taste  
acid dye  
      n   a dye in which the chromophore is part of a negative ion usually applied from an acidic solution  
acid-fast  
      adj   (of bacteria and tissues) resistant to decolorization by mineral acids after staining  
acid-forming  
      adj  
1    (of an oxide or element) yielding an acid when dissolved in water or having an oxide that forms an acid in water; acidic  
2    (of foods) producing an acid residue following digestion  
acid halide  
      n      another name for       acyl halide  
Acid House   , Acid  
      n   a type of funk-based electronically edited disco music of the late 1980s, which has hypnotic sound effects and is associated with hippy culture and the use of the drug ecstasy  
     (C20: perhaps from acid (LSD) + House (music))  
acid rain  
      n   rain that contains a high concentration of pollutants, chiefly sulphur dioxide and nitrogen oxide, released into the atmosphere by the burning of fossil fuels such as coal or oil  
acid rock  
      n   a type of rock music characterized by electronically amplified bizarre instrumental effects  
     (C20: from acid (sense 3), alluding to its supposed inspiration by drug-induced states of consciousness)  
acid salt  
      n     (Chem)   a salt formed by partial replacement of the acidic hydrogen atoms of the parent acid  
acid soil  
      n   a soil that gives a pH reaction of below 7.2, found especially in cool moist areas where soluble bases are leached away  
acid test  
      n   a rigorous and conclusive test to establish worth or value  
the play passed the critic's acid test     
     (C19: from the testing of gold with nitric acid)  
acid value  
      n   the number of milligrams of potassium hydroxide required to neutralize the free fatty acid in one gram of a fat, oil, resin, etc.  
acrylic acid  
      n   a colourless corrosive pungent liquid, miscible with water, used in the manufacture of acrylic resins. Formula: CH2:CHCOOH,   (Systematic name)    propenoic acid  
adenylic acid  
      n   a nucleotide consisting of adenine, ribose or deoxyribose, and a phosphate group. It is a constituent of DNA or RNA,   (Also called)    adenosine monophosphate  
adipic acid  
      n   a colourless crystalline solid used in the preparation of nylon. Formula: HOOC(CH2)4COOH  
     (C19: from New Latin adiposus fat + -ic)  
alginic acid  
      n   a white or yellowish powdery polysaccharide having marked hydrophilic properties. Extracted from kelp, it is used mainly in the food and textile industries and in cosmetics and pharmaceuticals. Formula: (C6H8O6)n; molecular wt.: 32000--250000  
amino acid  
      n   any of a group of organic compounds containing one or more amino groups, -NH2, and one or more carboxyl groups, -COOH. The alpha-amino acids RCH(NH2)COOH (where R is either hydrogen or an organic group) are the component molecules of proteins; some can be synthesized in the body (nonessential amino acids) and others cannot and are thus essential components of the diet (essential amino acids)  
amino acid sequence  
      n   the unique sequence of amino acids that characterizes a given protein  
aminobenzoic acid  
      n   a derivative of benzoic acid existing in three isomeric forms, the para- form being used in the manufacture of dyes and sunburn preventatives. Formula: NH2C6H4COOH  
arachidonic acid  
      n   a fatty acid occurring in animal cells: the metabolic precursor of several groups of biologically active substances, including prostaglandins  
arsenic acid  
      n   a white poisonous soluble crystalline solid used in the manufacture of arsenates and insecticides. Formula: H3AsO4  
ascorbic acid  
      n   a white crystalline vitamin present in plants, esp. citrus fruits, tomatoes, and green vegetables. A deficiency in the diet of man leads to scurvy. Formula: C6H8O6,   (Also called)    vitamin C  
     (C20 ascorbic from a-1 + scorb(ut)ic)  
aspartic acid  
      n   a nonessential amino acid that is a component of proteins and acts as a neurotransmitter  
     (C19: from aspar(agus) + -ic)  
barbituric acid  
      n   a white crystalline solid used in the preparation of barbiturate drugs. Formula: C4H4N2O3,   (Also called)    malonylurea  
     (C19: partial translation of German Barbitursäure, perhaps from the name Barbara + uric + Säure acid)  
benzenecarboxylic acid  
      n      the systematic name for       benzoic acid  
benzoic acid  
      n   a white crystalline solid occurring in many natural resins, used in the manufacture of benzoates, plasticizers, and dyes and as a food preservative (E210). Formula: C6H5COOH,   (Systematic name)    benzenecarboxylic acid  
boric acid  
      n  
1      (Also called)    orthoboric acid     (Systematic name)    trioxoboric(III) acid   a white soluble weakly acid crystalline solid used in the manufacture of heat-resistant glass and porcelain enamels, as a fireproofing material, and as a mild antiseptic. Formula: H3BO3  
2    any other acid containing boron  
bromic acid  
      n   a colourless unstable water-soluble liquid used as an oxidizing agent in the manufacture of dyes and pharmaceuticals. Formula: HBrO3  
butenedioic acid  
      n   either of two geometrical isomers with the formula HOOCCH:CHCOOH  
   See       fumaric acid       maleic acid  
butyric acid  
      n   a carboxylic acid existing in two isomeric forms, one of which produces the smell in rancid butter. Its esters are used in flavouring. Formula: C3(CH2)2COOH  
     (C19 butyric, from Latin butyrum butter)  
capric acid  
      n      another name for       decanoic acid  
     (C19: from Latin caper goat, so named from its smell)  
caproic acid  
      n      another name for       hexanoic acid  
     (C19: caproic, from Latin caper goat, alluding to its smell)  
carbamic acid  
      n   a hypothetical compound known only in the form of carbamate salts and esters. Formula: NH2COOH  
carbolic acid  
      n      another name for       phenol   esp. when it is used as an antiseptic or disinfectant   esp. when it is used as an antiseptic or disinfectant  
     (C19: carbolic, from carbo- + -ol1 + -ic)  
carbonic acid  
      n   a weak acid formed when carbon dioxide combines with water: obtained only in aqueous solutions, never in the pure state. Formula: H2CO3  
carbonic-acid gas  
      n      another name for       carbon dioxide  
carboxylic acid  
      n   any of a class of organic acids containing the carboxyl group  
   See also       fatty acid  
Caro's acid  
      n      another name for       peroxysulphuric acid  
     (C19: named after Heinrich Caro (died 1910), German chemist)  
cerotic acid  
      n      another name (not in technical usage) for       hexacosanoic acid  
chloric acid  
      n   a strong acid with a pungent smell, known only in solution and in the form of chlorate salts. Formula: HClO3  
chloroacetic acid   , chloracetic acid  
      n  
1    a colourless crystalline soluble strong acid prepared by chlorinating acetic acid and used as an intermediate in the manufacture of many chemicals; monochloracetic acid. Formula: CH2ClCOOH  
2    either of two related compounds: dichloracetic acid, CHCl2COOH, or trichloracetic acid CCl3COOH  
chlorous acid  
      n   an unstable acid that is a strong oxidizing agent. Formula: HClO2  
cholic acid  
      n   a crystalline insoluble acid present in bile: used as an emulsifying agent and an intermediate in the synthesis of organic compounds. Formula: C24H40O5  
     (C19: from Greek kholikos; see chole-)  
chromic acid  
      n   an unstable dibasic oxidizing acid known only in solution and in the form of chromate salts. Formula: H2CrO4  
cinnamic acid  
      n   a white crystalline water-insoluble weak organic acid existing in two isomeric forms; 3-phenylpropenoic acid. The trans- form occurs naturally and its esters are used in perfumery. Formula: C6H5CH:CHCOOH  
     (C19: from cinnam(on) + -ic; from its being found in cinnamon oil)  
citric acid  
      n   a water-soluble weak tribasic acid found in many fruits, esp. citrus fruits, and used in pharmaceuticals and as a flavouring (E330). It is extracted from citrus fruits or made by fermenting molasses and is an intermediate in carbohydrate metabolism. Formula: CH2(COOH)C(OH)(COOH)CH2COOH  
citric acid cycle  
      n      another name for       Krebs cycle  
crassulacean acid metabolism  
      n      the full name for       CAM       2  
crotonic acid  
      n   a colourless crystalline insoluble unsaturated carboxylic acid produced by oxidation of crotonaldehyde and used in organic synthesis; trans-2-butenoic acid. Formula: CH3CH:CHCOOH  
cyanic acid  
      n   a colourless poisonous volatile liquid acid that hydrolyses readily to ammonia and carbon dioxide. Formula: HOCN  
   Compare       isocyanic acid       fulminic acid  
cytidylic acid  
      n   a nucleotide consisting of cytosine, ribose or deoxyribose, and a phosphate group. It is a constituent of DNA or RNA,   (Also called)    cytidine monophosphate  
decanedioic acid  
      n   a white crystalline carboxylic acid obtained by heating castor oil with sodium hydroxide, used in the manufacture of polyester resins and rubbers and plasticizers. Formula: HOOC(CH2)8COOH,   (Also called)    sebacic acid  
decanoic acid  
      n   a white crystalline insoluble carboxylic acid with an unpleasant odour, used in perfumes and for making fruit flavours. Formula: C9H19COOH,   (Also called)    capric acid  
deoxyribonucleic acid   , desoxyribonucleic acid  
      n      the full name for       DNA  
dicarboxylic acid  
      n   any carboxylic acid that contains two carboxyl groups per molecule  
dichromic acid  
      n   an unstable dibasic oxidizing acid known only in solution and in the form of dichromate salts. Formula: H2Cr2O7  
disulphuric acid  
      n      another name for       pyrosulphuric acid  
dithionous acid  
      n   an unstable dibasic acid known only in solution and in the form of dithionite salts. It is a powerful reducing agent. Formula: H2S2O4,   (Also called)    hyposulphurous acid, hydrosulphurous acid  
     (from di-1 + thion-, from Greek theion sulphur + -ous)  
dodecanoic acid  
      n   a crystalline fatty acid found as glycerides in many vegetable oils: used in making soaps, insecticides, and synthetic resins. Formula: CH3(CH2)10COOH,   (Also called)    lauric acid  
     (C20: from dodecane (see dodeca-, -ane))  
erucic acid  
      adj  
      n   a crystalline fatty acid derived from the oils of rapeseed, mustard seed, and wallflower seed  
ethanedioic acid  
      n      the technical name for       oxalic acid  
     (C20: from ethane + di-1 + -o- + -ic)  
ethanoic acid  
      n      the modern name for       acetic acid  
fatty acid  
      n  
1    any of a class of aliphatic carboxylic acids, such as palmitic acid, stearic acid, and oleic acid, that form part of a lipid molecule  
2       another name for       carboxylic acid   esp. a naturally occurring one   esp. a naturally occurring one  
ferricyanic acid  
      n   a brown soluble unstable solid tribasic acid, usually known in the form of ferricyanide salts. Formula: H3Fe(CN)6  
ferrocyanic acid  
      n   a white volatile unstable solid tetrabasic acid, usually known in the form of ferrocyanide salts. Formula: H4Fe(CN)6  
folic acid  
      n   any of a group of vitamins of the B complex, including pteroylglutamic acid and its derivatives: used in the treatment of megaloblastic anaemia,   (Also called)    folacin  
     (C20: from Latin folium leaf; so called because it may be obtained from green leaves)  
formic acid  
      n   a colourless corrosive liquid carboxylic acid found in some insects, esp. ants, and many plants: used in dyeing textiles and the manufacture of insecticides and refrigerants. Formula: HCOOH,   (Systematic name)    methanoic acid  
fulminic acid  
      n   an unstable volatile acid known only in solution and in the form of its salts and esters. Formula: HONC  
   Compare       cyanic acid  
     (C19: from Latin fulmen lightning)  
fumaric acid  
      n   a colourless crystalline acid with a fruity taste, found in some plants and manufactured from benzene; trans-butenedioic acid: used esp. in synthetic resins. Formula: HCOOCH:CHCOOH  
     (C19: from New Latin Fumaria name of genus, from Late Latin: fumitory, from Latin fumus smoke)  
fuming sulphuric acid  
      n   a mixture of pyrosulphuric acid, H2S2O7, and other condensed acids, made by dissolving sulphur trioxide in concentrated sulphuric acid,   (Also called)    oleum, Nordhausen acid  
gallic acid  
      n   a colourless crystalline compound obtained from tannin: used as a tanning agent and in making inks, paper, and pyrogallol; 3,4,5-trihydroxybenzoic acid. Formula: C6H2(OH)3COOH  
gamma-aminobutyric acid  
      n      the full name for       GABA  
gibberellic acid  
      n   a slightly soluble crystalline plant hormone first isolated from the fungus Gibberella fujikuroi: a giberellin. Formula: C19H22O6  
     (C20: from New Latin Gibberella, literally: a little hump, from Latin gibber hump + -ic)  
glacial acetic acid  
      n   pure acetic acid (more than 99.8 per cent)  
glutamic acid   , glutaminic acid  
      n   a nonessential amino acid, occurring in proteins, that acts as a neurotransmitter and plays a part in nitrogen metabolism  
glyceric acid  
      n   a viscous liquid carboxylic acid produced by the oxidation of glycerol; 2,3-dihydroxypropanoic acid. Formula: C3H6O4  
glycolic acid  
      n   a colourless crystalline soluble hygroscopic compound found in sugar cane and sugar beet: used in tanning and in the manufacture of pharmaceuticals, pesticides, adhesives, and plasticizers; hydroxyacetic acid. Formula: CH2(OH)COOH  
guanylic acid  
      n   a nucleotide consisting of guanine, ribose or deoxyribose, and a phosphate group. It is a constituent of DNA or RNA,   (Also called)    guanosine monophosphate  
heptadecanoic acid  
      n   a colourless crystalline water-insoluble carboxylic acid used in organic synthesis. Formula: CH3(CH2)15COOH,   (Also called)    margaric acid  
hexacosanoic acid  
      n   a white insoluble odourless wax present in beeswax, carnauba, and Chinese wax. Formula: CH3(CH2)24COOH,   (Also called)    cerotic acid  
hexadecanoic acid  
      n      the systematic name for       palmitic acid  
hexanoic acid  
      n   an insoluble oily carboxylic acid found in coconut and palm oils and in milk. Formula: C5H11COOH  
     (C20: from hexane + -oic)  
hippuric acid  
      n   a crystalline solid excreted in the urine of mammals. Formula: C9H9NO3  
hyaluronic acid  
      n   a viscous polysaccharide with important lubricating properties, present, for example, in the synovial fluid in joints  
     (C20: hyalo- + Greek ouron urine + -ic)  
  hyaluronic      adj  
hydnocarpic acid  
      n   a cyclic fatty acid occurring in the form of its glycerides in chaulmoogra oil. Formula: C16H28O2  
     (C20: from Greek hudnon truffle + karpos fruit + -ic)  
hydrazoic acid  
      n   a colourless highly explosive liquid. Formula: HN3  
   See also       azide  
hydriodic acid  
      n   the colourless or pale yellow aqueous solution of hydrogen iodide: a strong acid  
     (C19: from hydro- + iodic)  
hydrobromic acid  
      n   the colourless or faintly yellow aqueous solution of hydrogen bromide: a strong acid  
hydrochloric acid  
      n   the colourless or slightly yellow aqueous solution of hydrogen chloride: a strong acid used in many industrial and laboratory processes,   (Formerly called)    muriatic acid  
hydrocyanic acid  
      n      another name for       hydrogen cyanide   esp. when in aqueous solution   esp. when in aqueous solution  
hydrofluoric acid  
      n   the colourless aqueous solution of hydrogen fluoride: a strong acid that attacks glass  
hydrosulphurous acid  
      n      another name (not in technical usage) for       dithionous acid  
hydroxy acid  
      n  
1    any acid, such as sulphuric acid, containing hydroxyl groups in its molecules  
2    any of a class of carboxylic acids that contain both a hydroxyl group and a carboxyl group in their molecules  
hypochlorous acid  
      n   an unstable acid known only in solution and in the form of its salts, formed when chlorine dissolves in water: a strong oxidizing and bleaching agent. Formula: HOCl  
hyponitrous acid  
      n   a white soluble unstable crystalline acid: an oxidizing and reducing agent. Formula: H2N2O2  
hypophosphoric acid  
      n   a crystalline odourless deliquescent solid: a tetrabasic acid produced by the slow oxidation of phosphorus in moist air. Formula: H4P2O6  
hypophosphorous acid  
      n   a colourless or yellowish oily liquid or white deliquescent solid: a monobasic acid and a reducing agent. Formula: H3PO2  
hyposulphurous acid  
      n      another name for       dithionous acid  
indoleacetic acid  
      n   an auxin that causes elongation of the cells of plant stems. Formula: C10H9NO2,   (Abbrev.)    IAA  
indolebutyric acid  
      n   a synthetic auxin used for stimulating plant growth and root formation. Formula: C8H6N(CH2)3COOH  
iodic acid  
      n   a colourless or pale yellow soluble crystalline substance that forms acidic aqueous solutions. Used as a reagent and disinfectant. Formula: HIO3  
isocyanic acid  
      n   a hypothetical acid known only in the form of its compounds. Formula: HNCO  
itaconic acid  
      n   a white colourless crystalline carboxylic acid obtained by the fermentation of carbohydrates and used in the manufacture of synthetic resins. Formula: CH2:C(COOH)CH2COOH  
lactic acid  
      n   a colourless syrupy carboxylic acid found in sour milk and many fruits and used as a preservative (E270) for foodstuffs, such as soft margarine, and for making pharmaceuticals and adhesives. Formula: CH3CH(OH)COOH,   (Systematic name)    2-hydroxypropanoic acid  
lauric acid  
      n      another name for       dodecanoic acid  
     (C19: from Latin laurus laurel; from its occurrence in the berries of the laurel (Laurus nobilis))  
Lewis acid  
      n   a substance capable of accepting a pair of electrons from a base to form a covalent bond  
   Compare       Lewis base  
     (C20: named after G. N. Lewis (1875--1946), US chemist)  
linoleic acid  
      n   a colourless oily essential fatty acid found in many natural oils, such as linseed: used in the manufacture of soaps, emulsifiers, and driers. Formula: C18H32O2  
     (C19: from Latin linum flax + oleic acid; so named because it is found in linseed oil)  
linolenic acid  
      n   a colourless unsaturated essential fatty acid found in drying oils, such as linseed oil, and used in making paints and synthetic resins; 9,12,15-octadecatrienoic acid. Formula: C18H30O2  
lipoic acid  
      n     (Biochem)   a sulphur-containing fatty acid, regarded as an element of the vitamin B complex, minute amounts of which are required for carbohydrate metabolism  
lysergic acid  
      n   a crystalline compound with a polycyclic molecular structure: used in medical research. Formula C16H16N2O2  
     (C20: from (hydro)lys(is) + erg(ot) + -ic)  
lysergic acid diethylamide  
      n      See       LSD  
maleic acid  
      n   a colourless soluble crystalline substance used to synthesize other compounds. Formula: HOOCCH:CHCOOH,   (Systematic name)    cis-butanedioic acid  
     (C19: from French maléique, altered form of malique; see malic acid)  
malic acid  
      n   a colourless crystalline compound occurring in apples and other fruits. Formula: HOOCCH2CH(OH)COOH  
     (C18 malic, via French malique from Latin malum apple)  
malonic acid  
      n      another name for       propanedioic acid  
     (C19: from French malonique, altered form of malique; see malic acid)  
manganic acid  
      n   a hypothetical dibasic acid known only in solution and in the form of manganate salts. Formula: H2MnO4  
margaric acid  
      n      another name for       heptadecanoic acid  
metaphosphoric acid  
      n   a glassy deliquescent highly polymeric solid, used as a dehydrating agent. Formula: (HPO3)x  
   See also       polyphosphoric acid  
methacrylic acid  
      n   a colourless crystalline water-soluble substance used in the manufacture of acrylic resins; 2-methylpropenoic acid. Formula: CH2:C(CH3)COOH  
methanoic acid  
      n      the systematic name for       formic acid  
mucic acid  
      n   a colourless crystalline solid carboxylic acid found in milk sugar and used in the manufacture of pyrrole. Formula: C4H4(OH)4(COOH)2  
     (C19: mucic, from French mucique; see mucus, -ic)  
muriatic acid  
      n      a former name for       hydrochloric acid  
     (C17: from Latin muriaticus pickled, from muria brine)  
nicotinic acid  
      n   a vitamin of the B complex that occurs in milk, liver, yeast, etc. Lack of it in the diet leads to the disease pellagra. Formula: (C5H4N)COOH,   (Also called)    niacin  
nitric acid  
      n   a colourless or yellowish fuming corrosive liquid usually used in aqueous solution. It is an oxidizing agent and a strong monobasic acid: important in the manufacture of fertilizers, explosives, and many other chemicals. Formula: HNO3,   (Former name)    aqua fortis  
nitrohydrochloric acid  
      n      another name for       aqua regia  
nitrous acid  
      n   a weak monobasic acid known only in solution and in the form of nitrite salts. Formula: HNO2,   (Systematic name)    dioxonitric(III) acid  
nonanoic acid  
      n   a colourless oily fatty acid with a rancid odour: used in making pharmaceuticals, lacquers, and plastics. Formula: CH3(CH2)7COOH,   (Also called)    pelargonic acid  
     (C19: from nonane a paraffin, ninth in the methane series, from Latin nonus ninth + -ane)  
nucleic acid  
      n     (Biochem)   any of a group of complex compounds with a high molecular weight that are vital constituents of all living cells  
   See also       RNA       DNA  
octanedioic acid  
      n   a colourless crystalline dicarboxylic acid found in suberin and castor oil and used in the manufacture of synthetic resins. Formula: HOOC(CH2)6COOH,   (Also called)    suberic acid  
     (C20: from octane + diol)  
oleic acid  
      n   a colourless oily liquid unsaturated acid occurring, as the glyceride, in almost all natural fats used in making soaps, ointments, cosmetics, and lubricating oils. Formula: CH3(CH2)7CH:CH(CH2)7COOH,   (Systematic name)    cis-9-octadecenoic acid  
     (C19 oleic, from Latin oleum oil + -ic)  
orthoboric acid  
      n      the more formal name for       boric acid       1  
orthophosphoric acid  
      n   a colourless soluble solid tribasic acid used in the manufacture of fertilizers and soaps. Formula: H3PO4,   (Also called)    phosphoric acid  
orthophosphorous acid  
      n   a white or yellowish hygroscopic crystalline dibasic acid. Formula: H3PO3,   (Also called)    phosphorous acid  
oxalic acid  
      n   a colourless poisonous crystalline dicarboxylic acid found in many plants: used as a bleach and a cleansing agent for metals. Formula: (COOH)2,   (Systematic name)    ethanedioic acid  
     (C18: from French oxalique, from Latin oxalis garden sorrel; see oxalis)  
oxo acid  
      n      another name for       oxyacid  
oxygen acid  
      n      another name for       oxyacid  
palmitic acid  
      n   a white crystalline solid that is a saturated fatty acid: used in the manufacture of soap and candles. Formula: (C15H31)COOH,   (Systematic name)    hexadecanoic acid  
     (C19: from French palmitique; see palm2, -ite2, -ic)  
pantothenic acid  
      n   an oily acid that is a vitamin of the B complex: occurs widely in animal and vegetable foods and is essential for cell growth. Formula: C19H17NO5  
     (C20: from Greek pantothen from every side)  
para-aminobenzoic acid  
      n     (Biochem)   an acid present in yeast and liver: used in the manufacture of dyes and pharmaceuticals. Formula: C6H4(NH2)COOH  
pectic acid  
      n   a complex acid containing arabinose and galactose that occurs in ripe fruit, beets, and other vegetables. Formula: C35H50O33  
pelargonic acid  
      n      another name for       nonanoic acid  
     (C19: so named because it was originally derived from pelargonium leaves)  
pentanoic acid  
      n   a colourless liquid carboxylic acid with an unpleasant odour, used in making perfumes, flavourings, and pharmaceuticals. Formula: CH3(CH2)3COOH,   (Also called)    valeric acid  
     (from pentane)  
perchloric acid  
      n   a colourless syrupy oxyacid of chlorine containing a greater proportion of oxygen than chloric acid. It is a powerful oxidizing agent and is used as a laboratory reagent. Formula: HClO4,   (Systematic name)    chloric(VII) acid  
periodic acid  
      n   any of various oxyacids of iodine containing a greater proportion of oxygen than iodic acid and differing from each other in water content, esp. either of the crystalline compounds HIO4 (metaperiodic acid) and H5IO6 (paraperiodic acid)  
     (C19: from per- + iodic)  
permanganic acid  
      n   a monobasic acid known only in solution and in the form of permanganate salts. Formula: HMnO4,   (Systematic name)    manganic(VII) acid  
peroxysulphuric acid  
      n   a white hygroscopic crystalline unstable oxidizing acid. Formula: H2SO5,   (Also called (not in technical usage))    persulphuric acid, Caros acid  
persulphuric acid   ,   (U.S.)   persulfuric acid  
      n      other names (not in technical usage) for       peroxysulphuric acid  
phosphonic acid  
      n      the systematic name for       phosphorous acid  
phosphoric acid  
      n  
1    a colourless solid tribasic acid used in the manufacture of fertilizers and soap. Formula: H3PO4,   (Systematic name)    phosphoric(V) acid     (Also called)    orthophosphoric acid  
2    any oxyacid of phosphorus produced by reaction between phosphorus pentoxide and water  
   See also       metaphosphoric acid       pyrophosphoric acid       hypophosphoric acid  
phosphorous acid  
      n  
1    a white or yellowish hygroscopic crystalline dibasic acid. Formula: H3PO3,   (Systematic name)    phosphoric acid     (Also called)    orthophosphorous acid  
2    any oxyacid of phosphorus containing less oxygen than the corresponding phosphoric acid  
phthalic acid  
      n   a soluble colourless crystalline acid used in the synthesis of dyes and perfumes; 1,2-benzenedicarboxylic acid. Formula: C6H4(COOH)2  
     (C19 phthalic, from phthal- (see phthalein) + -ic)  
picric acid  
      n   a toxic sparingly soluble crystalline yellow acid used as a dye, antiseptic, and explosive. Formula: C6H2OH(NO2)3,   (Systematic name)    2,4,6-trinitrophenol      See also       lyddite  
platinocyanic acid  
      n   a hypothetical tetrabasic acid known only in the form of platinocyanide salts. Formula: H2Pt(CN)4  
polycarboxylic acid  
      n   a type of carboxylic acid containing two or more carboxyl groups  
polyphosphoric acid  
      n  
1    any one of a series of oxyacids of phosphorus with the general formula Hn+2PnO3n+1. The first member is pyrophosphoric acid (n = 2) and the series includes the highly polymeric metaphosphoric acid. The higher acids exist in an equilibrium mixture  
2    a glassy or liquid mixture of orthophosphoric and polyphosphoric acids: used industrially as a dehydrating agent, catalyst, and oxidizing agent  
propanedioic acid  
      n   a colourless crystalline compound occurring in sugar beet. Formula: C3H4O4,CH2(COOH)2,   (Also called)    malonic acid  
     (C20: from propane + di-1 + -o- + -ic)  
propanoic acid  
      n   a colourless liquid carboxylic acid used in inhibiting the growth of moulds in bread. Formula: CH3CH2COOH,   (Former name)    propionic acid  
     (C20: from propane + -o- + -ic)  
propionic acid  
      n      the former name for       propanoic acid  
     (C19: from Greek pro- first + pionic from pion fat, because it is first in order of the fatty acids)  
prussic acid  
      n   the weakly acidic extremely poisonous aqueous solution of hydrogen cyanide  
     (C18: from French acide prussique Prussian acid, so called because obtained from Prussian blue)  
pyroligneous acid  
      n   the crude reddish-brown acidic liquid obtained by the distillation of wood and containing acetic acid, methanol, and acetone,   (Also called)    wood vinegar  
pyrophosphoric acid  
      n   a crystalline soluble solid acid formed by the reaction between one molecule of phosphorus pentoxide and two water molecules. Formula: H4P2O7  
   See also       polyphosphoric acid  
pyrosulphuric acid  
      n   a fuming liquid acid made by adding sulphur trioxide to concentrated sulphuric acid. Formula: H2S2O7,   (Also called)    disulphuric acid      See also       fuming sulphuric acid  
pyruvic acid  
      n   a colourless pleasant-smelling liquid formed as an intermediate in the metabolism of proteins and carbohydrates, helping to release energy to the body; 2-oxopropanoic acid. Formula: CH3COCOOH  
     (C19: pyruvic from pyro- + Latin uva grape)  
quinic acid  
      n   a white crystalline soluble optically active carboxylic acid, found in cinchona bark, bilberries, coffee beans, and the leaves of certain other plants; 1,3,4,5-tetrahydroxycyclohexanecarboxylic acid. Formula: C6H7(OH)4COOH  
racemic acid  
      n   the optically inactive form of tartaric acid that is sometimes found in grape juice  
ribonucleic acid  
      n      the full name of       RNA  
     (C20: from ribo(se) + nucleic acid)  
ricinoleic acid  
      n  
1    an oily unsaturated carboxylic acid found, as the glyceride, in castor oil and used in the manufacture of soap and in finishing textiles; 12-hydroxy-9-octadecanoic acid. Formula: C18H34O3  
2    the mixture of fatty acids obtained by hydrolysing castor oil  
     (C19: from ricin + oleic acid)  
saccharic acid  
      n   a white soluble solid dicarboxylic acid obtained by the oxidation of cane sugar or starch; 2,3,4,5-tetrahydroxyhexanedioic acid. Formula: COOH(CHOH)4COOH  
salicylic acid  
      n   a white crystalline slightly water-soluble substance with a sweet taste and bitter aftertaste, used in the manufacture of aspirin, dyes, and perfumes, and as a fungicide. Formula: C6H4(OH)(COOH)  
     (C19: from salicyl (via French from Latin salix a willow + -yl) + -ic)  
sebacic acid  
      n      another name for       decanedioic acid  
selenic acid  
      n   a colourless crystalline soluble strong dibasic acid analogous to sulphuric acid. Formula: H2SeO4  
selenious acid  
      n   a white soluble crystalline strong dibasic acid analogous to sulphurous acid. Formula: H2SeO3  
silicic acid  
      n   a white gelatinous substance obtained by adding an acid to a solution of sodium silicate. It has an ill-defined composition and is best regarded as hydrated silica, SiO2.nH2O  
sorbic acid  
      n   a white crystalline unsaturated carboxylic acid found in berries of the mountain ash and used to inhibit the growth of moulds and as an additive for certain synthetic coatings, as of cheese (E200); 2,4-hexadienoic acid. It exists as cis- and trans- isomers, the latter being the one usually obtained. Formula: CH3CH:CHCH:CHCOOH  
     (C19: from sorb (the tree), from its discovery in the berries of the mountain ash)  
stearic acid  
      n   a colourless odourless insoluble waxy carboxylic acid used for making candles and suppositories; octadecanoic acid. Formula: CH3(CH2)16COOH  
   See also       stearin       2  
suberic acid  
      n      another name for       octanedioic acid  
     (C18: from French subérique, from Latin suber cork (from which the acid is obtained))  
succinic acid  
      n   a colourless odourless water-soluble dicarboxylic acid found in plant and animal tissues: used in making lacquers, dyes, perfumes, etc.; 1,4-butanedioic acid. Formula: HOOCCH2:CH2COOH  
sulphonic acid  
      n   any of a large group of strong organic acids that contain the group --SO2OH and are used in the manufacture of dyes and drugs  
sulphuric acid  
      n   a colourless dense oily corrosive liquid produced by the reaction of sulphur trioxide with water and used in accumulators and in the manufacture of fertilizers, dyes, and explosives. Formula: H2SO4,   (Systematic name)    sulphuric(VI) acid  
sulphurous acid  
      n   an unstable acid produced when sulphur dioxide dissolves in water: used as a preservative for food and a bleaching agent. Formula: H2SO3,   (Systematic name)    sulphuric(IV) acid  
tantalic acid  
      n   a white gelatinous substance produced by hydrolysis of tantalic halides. It dissolves in strong bases to give tantalates  
tartaric acid  
      n   a colourless or white odourless crystalline water-soluble dicarboxylic acid existing in four stereoisomeric forms, the commonest being the dextrorotatory (d-) compound which is found in many fruits: used as a food additive (E334) in soft drinks, confectionery, and baking powders and in tanning and photography. Formula: HOOCCH(OH)CH(OH)COOH  
telluric acid  
      n   a white crystalline dibasic acid produced by the oxidation of tellurium by hydrogen peroxide. Formula: H6TeO6  
terebic acid  
      n   a white crystalline carboxylic acid produced by the action of nitric acid on turpentine. Formula: C7H10O4  
     (C19: from tereb(inth) + -ic)  
terephthalic acid  
      n   a white crystalline water-insoluble carboxylic acid used in making polyester resins such as Terylene; 1,4-benzenedicarboxylic acid. Formula: C6H4(COOH)2  
     (C20: from terebene + phthalic acid)  
thiocyanic acid  
      n   an unstable acid known in the form of thiocyanate salts. Formula: HSCN  
thiosulphuric acid  
      n   an unstable acid known only in solutions and in the form of its salts. Formula: H2S2O3  
thymidylic acid  
      n   a nucleotide consisting of thymine, deoxyribose, and a phosphate group. It is a constituent of DNA,   (Also called)    thymidine monophosphate  
tiglic acid  
      n   a syrupy liquid or crystalline colourless unsaturated carboxylic acid, with the trans-configuration, found in croton oil and used in perfumery; trans-2-methyl-2-butenoic acid. Formula: CH3CH:C(CH3)COOH  
     (C19 tiglic, from New Latin phrase Croton tiglium (name of the croton plant), of uncertain origin)  
titanic acid  
      n   any of various white substances regarded as hydrated forms of titanium dioxide, typical formulas being H4TiO4 and H2TiO3  
toluic acid  
      n   a white crystalline derivative of toluene existing in three isomeric forms; methylbenzoic acid. The ortho- and para- isomers are used in synthetic resins and the meta- isomer is used as an insect repellent. Formula: C6H4CH3COOH  
     (C19: from tolu(ene) + -ic)  
trans-fatty acid  
      n   a polyunsaturated fatty acid that has been converted from the cis-form by hydrogenation: used in the manufacture of margarine  
tricarboxylic acid cycle  
      n     (Biochem)      another name for       Krebs cycle     (Abbrev.)    TCA cycle  
trichloroacetic acid  
      n   a corrosive deliquescent crystalline acid with a characteristic odour, used as a veterinary astringent and antiseptic. Formula: CCl3COOH  
trichlorophenoxyacetic acid  
      n   an insoluble crystalline solid; 2,4,5-trichlorophenoxyacetic acid. It is a plant hormone and is used as a weedkiller. Formula: C8H5Cl3O3,   (Also called)    2,4,5-T  
tungstic acid  
      n   any of various oxyacids of tungsten obtained by neutralizing alkaline solutions of tungstates. They are often polymeric substances, typical examples being H2WO4 (orthotungstic acid), H2W4O13 (metatungstic acid), and H10W12O14 (paratungstic acid)  
uric acid  
      n   a white odourless tasteless crystalline product of protein metabolism, present in the blood and urine; 2,6,8-trihydroxypurine. Formula: C5H4N4O3  
uridylic acid  
      n   a nucleotide consisting of uracil, ribose, and a phosphate group. It is a constituent of RNA,   (Also called)    uridine monophosphate  
valeric acid  
      n      another name for       pentanoic acid  
vanadic acid  
      n   any one of various oxyacids of vanadium, such as H3VO4 (orthovanadic acid), HVO4 (metavanadic acid), and H4V2O7 (pyrovanadic acid), known chiefly in the form of their vanadate salts  
xanthic acid  
      n   any of a class of organic sulphur-containing acids with the general formula ROC(S)SH, where R is an organic group. Their salts are the xanthates  
Dictionnaire anglais Collins English definition-Thesaurus  
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LSD  
      n   lysergic acid diethylamide; a crystalline compound prepared from lysergic acid, used in experimental medicine and taken illegally as a hallucinogenic drug,   (Informal name (as an illegal hallucinogen))    acid         


abietic acid  
      n   a yellowish powder occurring naturally as a constituent of rosin and used in lacquers, varnishes, and soap. Formula: C19H29COOH; melting pt.: 173°C  
     (C19 abietic, from Latin abiet-, from abies silver fir (the acid originally being extracted from the resin))  
acetic acid  
      n   a colourless pungent liquid, miscible with water, widely used in the manufacture of acetic anhydride, vinyl acetate, plastics, pharmaceuticals, dyes, etc. Formula: CH3COOH,   (Systematic name)    ethanoic acid             See also       glacial acetic acid       vinegar  
acetylsalicylic acid  
      n      the chemical name for       aspirin  
acid  
      n  
1    any substance that dissociates in water to yield a sour corrosive solution containing hydrogen ions, having a pH of less than 7, and turning litmus red  
   See also       Lewis acid  
2    a sour-tasting substance  
3       a slang name for       LSD  
      adj  
4      (Chem)  
a    of, derived from, or containing acid  
an acid radical     
b    being or having the properties of an acid  
sodium bicarbonate is an acid salt     
5    sharp or sour in taste  
6    cutting, sharp, or hurtful in speech, manner, etc.; vitriolic; caustic  
7    (of rain, snow, etc.) containing pollutant acids in solution  
8    (of igneous rocks) having a silica content of more than two thirds the total and containing at least one tenth quartz  
9      (Metallurgy)   of or made by a process in which the furnace or converter is lined with an acid material  
acid steel     
     (C17 (first used by Francis Bacon): from French acide or Latin acidus, from acere to be sour or sharp)  
  acidly      adv  
  acidness      n  
  acidy      adj  
acid anhydride  
      n      another name for       anhydride       3  
acid drop  
      n   a boiled sweet with a sharp taste  
acid dye  
      n   a dye in which the chromophore is part of a negative ion usually applied from an acidic solution  
acid-fast  
      adj   (of bacteria and tissues) resistant to decolorization by mineral acids after staining  
acid-forming  
      adj  
1    (of an oxide or element) yielding an acid when dissolved in water or having an oxide that forms an acid in water; acidic  
2    (of foods) producing an acid residue following digestion  
acid halide  
      n      another name for       acyl halide  
Acid House   , Acid  
      n   a type of funk-based electronically edited disco music of the late 1980s, which has hypnotic sound effects and is associated with hippy culture and the use of the drug ecstasy  
     (C20: perhaps from acid (LSD) + House (music))  
acid rain  
      n   rain that contains a high concentration of pollutants, chiefly sulphur dioxide and nitrogen oxide, released into the atmosphere by the burning of fossil fuels such as coal or oil  
acid rock  
      n   a type of rock music characterized by electronically amplified bizarre instrumental effects  
     (C20: from acid (sense 3), alluding to its supposed inspiration by drug-induced states of consciousness      )  
acid salt  
      n     (Chem)   a salt formed by partial replacement of the acidic hydrogen atoms of the parent acid  
acid soil  
      n   a soil that gives a pH reaction of below 7.2, found especially in cool moist areas where soluble bases are leached away  
acid test  
      n   a rigorous and conclusive test to establish worth or value  
the play passed the critic's acid test     
     (C19: from the testing of gold with nitric acid)  
acid value  
      n   the number of milligrams of potassium hydroxide required to neutralize the free fatty acid in one gram of a fat, oil, resin, etc.  
acrylic acid  
      n   a colourless corrosive pungent liquid, miscible with water, used in the manufacture of acrylic resins. Formula: CH2:CHCOOH,   (Systematic name)    propenoic acid         
adenylic acid  
      n   a nucleotide consisting of adenine, ribose or deoxyribose, and a phosphate group. It is a constituent of DNA or RNA,   (Also called)    adenosine monophosphate  
adipic acid  
      n   a colourless crystalline solid used in the preparation of nylon. Formula: HOOC(CH2)4COOH  
     (C19: from New Latin adiposus fat + -ic)  
alginic acid  
      n   a white or yellowish powdery polysaccharide having marked hydrophilic properties. Extracted from kelp, it is used mainly in the food and textile industries and in cosmetics and pharmaceuticals. Formula: (C6H8O6)n; molecular wt.: 32000--250000  
amino acid  
      n   any of a group of organic compounds containing one or more amino groups, -NH2, and one or more carboxyl groups, -COOH. The alpha-amino acids RCH(NH2)COOH (where R is either hydrogen or an organic group) are the component molecules of proteins; some can be synthesized in the body (nonessential amino acids) and others cannot and are thus essential components of the diet (essential amino acids)  
amino acid sequence  
      n   the unique sequence of amino acids that characterizes a given protein  
aminobenzoic acid  
      n   a derivative of benzoic acid existing in three isomeric forms, the para- form being used in the manufacture of dyes and sunburn preventatives. Formula: NH2C6H4COOH         
arachidonic acid  
      n   a fatty acid occurring in animal cells: the metabolic precursor of several groups of biologically active substances, including prostaglandins  
arsenic acid  
      n   a white poisonous soluble crystalline solid used in the manufacture of arsenates and insecticides. Formula: H3AsO4  
ascorbic acid  
      n   a white crystalline vitamin present in plants, esp. citrus fruits, tomatoes, and green vegetables. A deficiency in the diet of man leads to scurvy. Formula: C6H8O6,   (Also called)    vitamin C  
     (C20 ascorbic from a-1 + scorb(ut)ic)  
aspartic acid  
      n   a nonessential amino acid that is a component of proteins and acts as a neurotransmitter  
     (C19: from aspar(agus) + -ic)  
barbituric acid  
      n   a white crystalline solid used in the preparation of barbiturate drugs. Formula: C4H4N2O3,   (Also called)    malonylurea  
     (C19: partial translation of German Barbitursäure, perhaps from the name Barbara + uric + Säure acid)  
benzenecarboxylic acid  
      n      the systematic name for       benzoic acid  
benzoic acid  
      n   a white crystalline solid occurring in many natural resins, used in the manufacture of benzoates, plasticizers, and dyes and as a food preservative (E210). Formula: C6H5COOH,   (Systematic name)    benzenecarboxylic acid         
boric acid  
      n  
1      (Also called)    orthoboric acid            (Systematic name)    trioxoboric(III) acid   a white soluble weakly acid crystalline solid used in the manufacture of heat-resistant glass and porcelain enamels, as a fireproofing material, and as a mild antiseptic. Formula: H3BO3  
2    any other acid containing boron  
bromic acid  
      n   a colourless unstable water-soluble liquid used as an oxidizing agent in the manufacture of dyes and pharmaceuticals. Formula: HBrO3  
butenedioic acid  
      n   either of two geometrical isomers with the formula HOOCCH:CHCOOH  
   See       fumaric acid       maleic acid  
butyric acid  
      n   a carboxylic acid existing in two isomeric forms, one of which produces the smell in rancid butter. Its esters are used in flavouring. Formula: C3(CH2)2COOH  
     (C19 butyric, from Latin butyrum butter)  
capric acid  
      n      another name for       decanoic acid  
     (C19: from Latin caper goat, so named from its smell)  
caproic acid  
      n      another name for       hexanoic acid  
     (C19: caproic, from Latin caper goat, alluding to its smell)  
carbamic acid  
      n   a hypothetical compound known only in the form of carbamate salts and esters. Formula: NH2COOH  
carbolic acid  
      n      another name for       phenol   esp. when it is used as an antiseptic or disinfectant   esp. when it is used as an antiseptic or disinfectant  
     (C19: carbolic, from carbo- + -ol1 + -ic)  
carbonic acid  
      n   a weak acid formed when carbon dioxide combines with water: obtained only in aqueous solutions, never in the pure state. Formula: H2CO3  
carbonic-acid gas  
      n      another name for       carbon dioxide  
carboxylic acid  
      n   any of a class of organic acids containing the carboxyl group  
   See also       fatty acid  
Caro's acid  
      n      another name for       peroxysulphuric acid  
     (C19: named after Heinrich Caro (died 1910), German chemist)  
cerotic acid  
      n      another name (not in technical usage) for       hexacosanoic acid  
chloric acid  
      n   a strong acid with a pungent smell, known only in solution and in the form of chlorate salts. Formula: HClO3  
chloroacetic acid   , chloracetic acid  
      n  
1    a colourless crystalline soluble strong acid prepared by chlorinating acetic acid and used as an intermediate in the manufacture of many chemicals; monochloracetic acid. Formula: CH2ClCOOH  
2    either of two related compounds: dichloracetic acid, CHCl2COOH, or trichloracetic acid CCl3COOH  
chlorous acid  
      n   an unstable acid that is a strong oxidizing agent. Formula: HClO2  
cholic acid  
      n   a crystalline insoluble acid present in bile: used as an emulsifying agent and an intermediate in the synthesis of organic compounds. Formula: C24H40O5  
     (C19: from Greek kholikos; see chole-)  
chromic acid  
      n   an unstable dibasic oxidizing acid known only in solution and in the form of chromate salts. Formula: H2CrO4  
cinnamic acid  
      n   a white crystalline water-insoluble weak organic acid existing in two isomeric forms; 3-phenylpropenoic acid. The trans- form occurs naturally and its esters are used in perfumery. Formula: C6H5CH:CHCOOH  
     (C19: from cinnam(on) + -ic; from its being found in cinnamon oil)  
citric acid  
      n   a water-soluble weak tribasic acid found in many fruits, esp. citrus fruits, and used in pharmaceuticals and as a flavouring (E330). It is extracted from citrus fruits or made by fermenting molasses and is an intermediate in carbohydrate metabolism. Formula: CH2(COOH)C(OH)(COOH)CH2COOH  
citric acid cycle  
      n      another name for       Krebs cycle  
crassulacean acid metabolism  
      n      the full name for       CAM       2  
crotonic acid  
      n   a colourless crystalline insoluble unsaturated carboxylic acid produced by oxidation of crotonaldehyde and used in organic synthesis; trans-2-butenoic acid. Formula: CH3CH:CHCOOH  
cyanic acid  
      n   a colourless poisonous volatile liquid acid that hydrolyses readily to ammonia and carbon dioxide. Formula: HOCN  
   Compare       isocyanic acid       fulminic acid  
cytidylic acid  
      n   a nucleotide consisting of cytosine, ribose or deoxyribose, and a phosphate group. It is a constituent of DNA or RNA,   (Also called)    cytidine monophosphate  
decanedioic acid  
      n   a white crystalline carboxylic acid obtained by heating castor oil with sodium hydroxide, used in the manufacture of polyester resins and rubbers and plasticizers. Formula: HOOC(CH2)8COOH,   (Also called)    sebacic acid  
decanoic acid  
      n   a white crystalline insoluble carboxylic acid with an unpleasant odour, used in perfumes and for making fruit flavours. Formula: C9H19COOH,   (Also called)    capric acid  
deoxyribonucleic acid   , desoxyribonucleic acid  
      n      the full name for       DNA  
dicarboxylic acid  
      n   any carboxylic acid that contains two carboxyl groups per molecule  
dichromic acid  
      n   an unstable dibasic oxidizing acid known only in solution and in the form of dichromate salts. Formula: H2Cr2O7  
disulphuric acid  
      n      another name for       pyrosulphuric acid  
dithionous acid  
      n   an unstable dibasic acid known only in solution and in the form of dithionite salts. It is a powerful reducing agent. Formula: H2S2O4,   (Also called)    hyposulphurous acid, hydrosulphurous acid  
     (from di-1 + thion-, from Greek theion sulphur + -ous)  
dodecanoic acid  
      n   a crystalline fatty acid found as glycerides in many vegetable oils: used in making soaps, insecticides, and synthetic resins. Formula: CH3(CH2)10COOH,   (Also called)    lauric acid  
     (C20: from dodecane (see dodeca-, -ane))  
erucic acid  
      adj  
      n   a crystalline fatty acid derived from the oils of rapeseed, mustard seed, and wallflower seed  
ethanedioic acid  
      n      the technical name for       oxalic acid  
     (C20: from ethane + di-1 + -o- + -ic)  
ethanoic acid  
      n      the modern name for       acetic acid  
fatty acid  
      n  
1    any of a class of aliphatic carboxylic acids, such as palmitic acid, stearic acid, and oleic acid, that form part of a lipid molecule  
2       another name for       carboxylic acid   esp. a naturally occurring one   esp. a naturally occurring one  
ferricyanic acid  
      n   a brown soluble unstable solid tribasic acid, usually known in the form of ferricyanide salts. Formula: H3Fe(CN)6  
ferrocyanic acid  
      n   a white volatile unstable solid tetrabasic acid, usually known in the form of ferrocyanide salts. Formula: H4Fe(CN)6  
folic acid  
      n   any of a group of vitamins of the B complex, including pteroylglutamic acid and its derivatives: used in the treatment of megaloblastic anaemia      ,   (Also called)    folacin  
     (C20: from Latin folium leaf; so called because it may be obtained from green leaves)  
formic acid  
      n   a colourless corrosive liquid carboxylic acid found in some insects, esp. ants, and many plants: used in dyeing textiles and the manufacture of insecticides and refrigerants. Formula: HCOOH,   (Systematic name)    methanoic acid         
fulminic acid  
      n   an unstable volatile acid known only in solution and in the form of its salts and esters. Formula: HONC         
   Compare       cyanic acid  
     (C19: from Latin fulmen lightning)  
fumaric acid  
      n   a colourless crystalline acid with a fruity taste, found in some plants and manufactured from benzene; trans-butenedioic acid: used esp. in synthetic resins. Formula: HCOOCH:CHCOOH  
     (C19: from New Latin Fumaria name of genus, from Late Latin: fumitory, from Latin fumus smoke)  
fuming sulphuric acid  
      n   a mixture of pyrosulphuric acid, H2S2O7, and other condensed acids, made by dissolving sulphur trioxide in concentrated sulphuric acid,   (Also called)    oleum, Nordhausen acid  
gallic acid  
      n   a colourless crystalline compound obtained from tannin: used as a tanning agent and in making inks, paper, and pyrogallol; 3,4,5-trihydroxybenzoic acid. Formula: C6H2(OH)3COOH  
gamma-aminobutyric acid  
      n      the full name for       GABA  
gibberellic acid  
      n   a slightly soluble crystalline plant hormone first isolated from the fungus Gibberella fujikuroi: a giberellin. Formula: C19H22O6  
     (C20: from New Latin Gibberella, literally: a little hump, from Latin gibber hump + -ic)  
glacial acetic acid  
      n   pure acetic acid (more than 99.8 per cent)  
glutamic acid   , glutaminic acid  
      n   a nonessential amino acid, occurring in proteins, that acts as a neurotransmitter and plays a part in nitrogen metabolism  
glyceric acid  
      n   a viscous liquid carboxylic acid produced by the oxidation of glycerol; 2,3-dihydroxypropanoic acid. Formula: C3H6O4  
glycolic acid  
      n   a colourless crystalline soluble hygroscopic compound found in sugar cane and sugar beet: used in tanning and in the manufacture of pharmaceuticals, pesticides, adhesives, and plasticizers; hydroxyacetic acid. Formula: CH2(OH)COOH  
guanylic acid  
      n   a nucleotide consisting of guanine, ribose or deoxyribose, and a phosphate group. It is a constituent of DNA or RNA,   (Also called)    guanosine monophosphate  
heptadecanoic acid  
      n   a colourless crystalline water-insoluble carboxylic acid used in organic synthesis. Formula: CH3(CH2)15COOH,   (Also called)    margaric acid  
hexacosanoic acid  
      n   a white insoluble odourless wax present in beeswax, carnauba, and Chinese wax. Formula: CH3(CH2)24COOH,   (Also called)    cerotic acid  
hexadecanoic acid  
      n      the systematic name for       palmitic acid  
hexanoic acid  
      n   an insoluble oily carboxylic acid found in coconut and palm oils and in milk. Formula: C5H11COOH  
     (C20: from hexane + -oic)  
hippuric acid  
      n   a crystalline solid excreted in the urine of mammals. Formula: C9H9NO3  
hyaluronic acid  
      n   a viscous polysaccharide with important lubricating properties, present, for example, in the synovial fluid in joints  
     (C20: hyalo- + Greek ouron urine + -ic)  
  hyaluronic      adj  
hydnocarpic acid  
      n   a cyclic fatty acid occurring in the form of its glycerides in chaulmoogra oil. Formula: C16H28O2  
     (C20: from Greek hudnon truffle + karpos fruit + -ic)  
hydrazoic acid  
      n   a colourless highly explosive liquid. Formula: HN3  
   See also       azide  
hydriodic acid  
      n   the colourless or pale yellow aqueous solution of hydrogen iodide: a strong acid  
     (C19: from hydro- + iodic)  
hydrobromic acid  
      n   the colourless or faintly yellow aqueous solution of hydrogen bromide: a strong acid  
hydrochloric acid  
      n   the colourless or slightly yellow aqueous solution of hydrogen chloride: a strong acid used in many industrial and laboratory processes,   (Formerly called)    muriatic acid  
hydrocyanic acid  
      n      another name for       hydrogen cyanide   esp. when in aqueous solution   esp. when in aqueous solution  
hydrofluoric acid  
      n   the colourless aqueous solution of hydrogen fluoride: a strong acid that attacks glass  
hydrosulphurous acid  
      n      another name (not in technical usage) for       dithionous acid  
hydroxy acid  
      n  
1    any acid, such as sulphuric acid, containing hydroxyl groups in its molecules  
2    any of a class of carboxylic acids that contain both a hydroxyl group and a carboxyl group in their molecules  
hypochlorous acid  
      n   an unstable acid known only in solution and in the form of its salts, formed when chlorine dissolves in water: a strong oxidizing and bleaching agent. Formula: HOCl  
hyponitrous acid  
      n   a white soluble unstable crystalline acid: an oxidizing and reducing agent. Formula: H2N2O2  
hypophosphoric acid  
      n   a crystalline odourless deliquescent solid: a tetrabasic acid produced by the slow oxidation of phosphorus in moist air. Formula: H4P2O6  
hypophosphorous acid  
      n   a colourless or yellowish oily liquid or white deliquescent solid: a monobasic acid and a reducing agent. Formula: H3PO2  
hyposulphurous acid  
      n      another name for       dithionous acid  
indoleacetic acid  
      n   an auxin that causes elongation of the cells of plant stems. Formula: C10H9NO2,   (Abbrev.)    IAA  
indolebutyric acid  
      n   a synthetic auxin used for stimulating plant growth and root formation. Formula: C8H6N(CH2)3COOH  
iodic acid  
      n   a colourless or pale yellow soluble crystalline substance that forms acidic aqueous solutions. Used as a reagent and disinfectant. Formula: HIO3  
isocyanic acid  
      n   a hypothetical acid known only in the form of its compounds. Formula: HNCO  
itaconic acid  
      n   a white colourless crystalline carboxylic acid obtained by the fermentation of carbohydrates and used in the manufacture of synthetic resins. Formula: CH2:C(COOH)CH2COOH  
lactic acid  
      n   a colourless syrupy carboxylic acid found in sour milk and many fruits and used as a preservative (E270) for foodstuffs, such as soft margarine, and for making pharmaceuticals and adhesives. Formula: CH3CH(OH)COOH,   (Systematic name)    2-hydroxypropanoic acid         
lauric acid  
      n      another name for       dodecanoic acid  
     (C19: from Latin laurus laurel; from its occurrence in the berries of the laurel (Laurus nobilis))  
Lewis acid  
      n   a substance capable of accepting a pair of electrons from a base to form a covalent bond  
   Compare       Lewis base  
     (C20: named after G. N. Lewis (1875--1946), US chemist)  
linoleic acid  
      n   a colourless oily essential fatty acid found in many natural oils, such as linseed: used in the manufacture of soaps, emulsifiers, and driers. Formula: C18H32O2  
     (C19: from Latin linum flax + oleic acid; so named because it is found in linseed oil)  
linolenic acid  
      n   a colourless unsaturated essential fatty acid found in drying oils, such as linseed oil, and used in making paints and synthetic resins; 9,12,15-octadecatrienoic acid. Formula: C18H30O2               
lipoic acid  
      n     (Biochem)   a sulphur-containing fatty acid, regarded as an element of the vitamin B complex, minute amounts of which are required for carbohydrate metabolism  
lysergic acid  
      n   a crystalline compound with a polycyclic molecular structure: used in medical research. Formula C16H16N2O2  
     (C20: from (hydro)lys(is) + erg(ot) + -ic)  
lysergic acid diethylamide  
      n      See       LSD  
maleic acid  
      n   a colourless soluble crystalline substance used to synthesize other compounds. Formula: HOOCCH:CHCOOH,   (Systematic name)    cis-butanedioic acid  
     (C19: from French maléique, altered form of malique; see malic acid)  
malic acid  
      n   a colourless crystalline compound occurring in apples and other fruits. Formula: HOOCCH2CH(OH)COOH  
     (C18 malic, via French malique from Latin malum apple)  
malonic acid  
      n      another name for       propanedioic acid  
     (C19: from French malonique, altered form of malique; see malic acid)  
manganic acid  
      n   a hypothetical dibasic acid known only in solution and in the form of manganate salts. Formula: H2MnO4  
margaric acid  
      n      another name for        heptadecanoic acid         
metaphosphoric acid  
      n   a glassy deliquescent highly polymeric solid, used as a dehydrating agent. Formula: (HPO3)x  
   See also       polyphosphoric acid  
methacrylic acid  
      n   a colourless crystalline water-soluble substance used in the manufacture of acrylic resins; 2-methylpropenoic acid. Formula: CH2:C(CH3)COOH  
methanoic acid  
      n      the systematic name for       formic acid  
mucic acid  
      n   a colourless crystalline solid carboxylic acid found in milk sugar and used in the manufacture of pyrrole. Formula: C4H4(OH)4(COOH)2  
     (C19: mucic, from French mucique; see mucus, -ic)  
muriatic acid  
      n      a former name for       hydrochloric acid  
     (C17: from Latin muriaticus pickled, from muria brine)  
nicotinic acid  
      n   a vitamin of the B complex that occurs in milk, liver, yeast, etc. Lack of it in the diet leads to the disease pellagra. Formula: (C5H4N)COOH,   (Also called)    niacin  
nitric acid  
      n   a colourless or yellowish fuming corrosive liquid usually used in aqueous solution. It is an oxidizing agent and a strong monobasic acid: important in the manufacture of fertilizers, explosives, and many other chemicals. Formula: HNO3,   (Former name)    aqua fortis  
nitrohydrochloric acid  
      n      another name for       aqua regia  
nitrous acid  
      n   a weak monobasic acid known only in solution and in the form of nitrite salts. Formula: HNO2,   (Systematic name)    dioxonitric(III) acid         
nonanoic acid  
      n   a colourless oily fatty acid with a rancid odour: used in making pharmaceuticals, lacquers, and plastics. Formula: CH3(CH2)7COOH,   (Also called)    pelargonic acid  
     (C19: from nonane a paraffin, ninth in the methane series, from Latin nonus ninth + -ane)  
nucleic acid  
      n     (Biochem)   any of a group of complex compounds with a high molecular weight that are vital constituents of all living cells  
   See also       RNA       DNA  
octanedioic acid  
      n   a colourless crystalline dicarboxylic acid found in suberin and castor oil and used in the manufacture of synthetic resins. Formula: HOOC(CH2)6COOH,   (Also called)    suberic acid  
     (C20: from octane + diol)  
oleic acid  
      n   a colourless oily liquid unsaturated acid occurring, as the glyceride, in almost all natural fats used in making soaps, ointments, cosmetics, and lubricating oils. Formula: CH3(CH2)7CH:CH(CH2)7COOH,   (Systematic name)    cis-9-octadecenoic acid  
     (C19 oleic, from Latin oleum oil + -ic)  
orthoboric acid  
      n      the more formal name for       boric acid       1  
orthophosphoric acid  
      n   a colourless soluble solid tribasic acid used in the manufacture of fertilizers and soaps. Formula: H3PO4,   (Also called)    phosphoric acid  
orthophosphorous acid  
      n   a white or yellowish hygroscopic crystalline dibasic acid. Formula: H3PO3,   (Also called)    phosphorous acid  
oxalic acid  
      n   a colourless poisonous crystalline dicarboxylic acid found in many plants: used as a bleach and a cleansing agent for metals. Formula: (COOH)2,   (Systematic name)    ethanedioic acid  
     (C18: from French oxalique, from Latin oxalis garden sorrel; see oxalis)  
oxo acid  
      n      another name for       oxyacid  
oxygen acid  
      n      another name for       oxyacid  
palmitic acid  
      n   a white crystalline solid that is a saturated fatty acid: used in the manufacture of soap and candles. Formula: (C15H31)COOH,   (Systematic name)    hexadecanoic acid  
     (C19: from French palmitique; see palm2, -ite2, -ic)  
pantothenic acid  
      n   an oily acid that is a vitamin of the B complex: occurs widely in animal and vegetable foods and is essential for cell growth. Formula: C19H17NO5  
     (C20: from Greek pantothen from every side)  
para-aminobenzoic acid  
      n     (Biochem)   an acid present in yeast and liver: used in the manufacture of dyes and pharmaceuticals. Formula: C6H4(NH2)COOH  
pectic acid  
      n   a complex acid containing arabinose and galactose that occurs in ripe fruit, beets, and other vegetables. Formula: C35H50O33  
pelargonic acid  
      n      another name for       nonanoic acid  
     (C19: so named because it was originally derived from pelargonium leaves)  
pentanoic acid  
      n   a colourless liquid carboxylic acid with an unpleasant odour, used in making perfumes, flavourings, and pharmaceuticals. Formula: CH3(CH2)3COOH,   (Also called)    valeric acid  
     (from pentane)  
perchloric acid  
      n   a colourless syrupy oxyacid of chlorine containing a greater proportion of oxygen than chloric acid. It is a powerful oxidizing agent and is used as a laboratory reagent. Formula: HClO4,   (Systematic name)    chloric(VII) acid  
periodic acid  
      n   any of various oxyacids of iodine containing a greater proportion of oxygen than iodic acid and differing from each other in water content, esp. either of the crystalline compounds HIO4 (metaperiodic acid) and H5IO6 (paraperiodic acid)  
     (C19: from per- + iodic)  
permanganic acid  
      n   a monobasic acid known only in solution and in the form of permanganate salts. Formula: HMnO4,   (Systematic name)    manganic(VII) acid  
peroxysulphuric acid  
      n   a white hygroscopic crystalline unstable oxidizing acid. Formula: H2SO5,   (Also called (not in technical usage))    persulphuric acid, Caros acid  
persulphuric acid   ,   (U.S.)   persulfuric acid  
      n      other names (not in technical usage) for       peroxysulphuric acid  
phosphonic acid  
      n      the systematic name for       phosphorous acid  
phosphoric acid  
      n  
1    a colourless solid tribasic acid used in the manufacture of fertilizers and soap. Formula: H3PO4,   (Systematic name)    phosphoric(V) acid     (Also called)    orthophosphoric acid  
2    any oxyacid of phosphorus produced by reaction between phosphorus pentoxide and water  
   See also       metaphosphoric acid       pyrophosphoric acid       hypophosphoric acid  
phosphorous acid  
      n  
1    a white or yellowish hygroscopic crystalline dibasic acid. Formula: H3PO3,   (Systematic name)    phosphoric acid     (Also called)    orthophosphorous acid  
2    any oxyacid of phosphorus containing less oxygen than the corresponding phosphoric acid  
phthalic acid  
      n   a soluble colourless crystalline acid used in the synthesis of dyes and perfumes; 1,2-benzenedicarboxylic acid. Formula: C6H4(COOH)2               
     (C19 phthalic, from phthal- (see phthalein) + -ic)  
picric acid  
      n   a toxic sparingly soluble crystalline yellow acid used as a dye, antiseptic, and explosive. Formula: C6H2OH(NO2)3,   (Systematic name)    2,4,6-trinitrophenol      See also       lyddite  
platinocyanic acid  
      n   a hypothetical tetrabasic acid known only in the form of platinocyanide salts. Formula: H2Pt(CN)4  
polycarboxylic acid  
      n   a type of carboxylic acid containing two or more carboxyl groups  
polyphosphoric acid  
      n  
1    any one of a series of oxyacids of phosphorus with the general formula Hn+2PnO3n+1. The first member is pyrophosphoric acid (n = 2) and the series includes the highly polymeric metaphosphoric acid. The higher acids exist in an equilibrium mixture               
2    a glassy or liquid mixture of orthophosphoric and polyphosphoric acids: used industrially as a dehydrating agent, catalyst, and oxidizing agent  
propanedioic acid  
      n   a colourless crystalline compound occurring in sugar beet. Formula: C3H4O4,CH2(COOH)2,   (Also called)    malonic acid  
     (C20: from propane + di-1 + -o- + -ic)  
propanoic acid  
      n   a colourless liquid carboxylic acid used in inhibiting the growth of moulds in bread. Formula: CH3CH2COOH,   (Former name)    propionic acid  
     (C20: from propane + -o- + -ic)  
propionic acid  
      n      the former name for       propanoic acid  
     (C19: from Greek pro- first + pionic from pion fat, because it is first in order of the fatty acids)  
prussic acid  
      n   the weakly acidic extremely poisonous aqueous solution of hydrogen cyanide  
     (C18: from French acide prussique Prussian acid, so called because obtained from Prussian blue)  
pyroligneous acid  
      n   the crude reddish-brown acidic liquid obtained by the distillation of wood and containing acetic acid, methanol, and acetone,   (Also called)    wood vinegar  
pyrophosphoric acid  
      n   a crystalline soluble solid acid formed by the reaction between one molecule of phosphorus pentoxide and two water molecules. Formula: H4P2O7  
   See also       polyphosphoric acid  
pyrosulphuric acid  
      n   a fuming liquid acid made by adding sulphur trioxide to concentrated sulphuric acid. Formula: H2S2O7,   (Also called)    disulphuric acid      See also       fuming sulphuric acid  
pyruvic acid  
      n   a colourless pleasant-smelling liquid formed as an intermediate in the metabolism of proteins and carbohydrates, helping to release energy to the body; 2-oxopropanoic acid. Formula: CH3COCOOH  
     (C19: pyruvic from pyro- + Latin uva grape)  
quinic acid  
      n   a white crystalline soluble optically active carboxylic acid, found in cinchona bark, bilberries, coffee beans, and the leaves of certain other plants; 1,3,4,5-tetrahydroxycyclohexanecarboxylic acid. Formula: C6H7(OH)4COOH  
racemic acid  
      n   the optically inactive form of tartaric acid that is sometimes found in grape juice  
ribonucleic acid  
      n      the full name of       RNA  
     (C20: from ribo(se) + nucleic acid)  
ricinoleic acid  
      n  
1    an oily unsaturated carboxylic acid found, as the glyceride, in castor oil and used in the manufacture of soap and in finishing textiles; 12-hydroxy-9-octadecanoic acid. Formula: C18H34O3  
2    the mixture of fatty acids obtained by hydrolysing castor oil  
     (C19: from ricin + oleic acid)  
saccharic acid  
      n   a white soluble solid dicarboxylic acid obtained by the oxidation of cane sugar or starch; 2,3,4,5-tetrahydroxyhexanedioic acid. Formula: COOH(CHOH)4COOH  
salicylic acid  
      n   a white crystalline slightly water-soluble substance with a sweet taste and bitter aftertaste, used in the manufacture of aspirin, dyes, and perfumes, and as a fungicide. Formula: C6H4(OH)(COOH)  
     (C19: from salicyl (via French from Latin salix a willow + -yl) + -ic)  
sebacic acid  
      n      another name for       decanedioic acid  
selenic acid  
      n   a colourless crystalline soluble strong dibasic acid analogous to sulphuric acid. Formula: H2SeO4  
selenious acid  
      n   a white soluble crystalline strong dibasic acid analogous to sulphurous acid. Formula: H2SeO3  
silicic acid  
      n   a white gelatinous substance obtained by adding an acid to a solution of sodium silicate. It has an ill-defined composition and is best regarded as hydrated silica, SiO2.nH2O  
sorbic acid  
      n   a white crystalline unsaturated carboxylic acid found in berries of the mountain ash and used to inhibit the growth of moulds and as an additive for certain synthetic coatings, as of cheese (E200); 2,4-hexadienoic acid. It exists as cis- and trans- isomers, the latter being the one usually obtained. Formula: CH3CH:CHCH:CHCOOH  
     (C19: from sorb (the tree), from its discovery in the berries of the mountain ash)  
stearic acid  
      n   a colourless odourless insoluble waxy carboxylic acid used for making candles and suppositories; octadecanoic acid. Formula: CH3(CH2)16COOH  
   See also       stearin       2  
suberic acid  
      n      another name for       octanedioic acid  
     (C18: from French subérique, from Latin suber cork (from which the acid is obtained))  
succinic acid  
      n   a colourless odourless water-soluble dicarboxylic acid found in plant and animal tissues: used in making lacquers, dyes, perfumes, etc.; 1,4-butanedioic acid. Formula: HOOCCH2:CH2COOH  
sulphonic acid  
      n   any of a large group of strong organic acids that contain the group --SO2OH and are used in the manufacture of dyes and drugs  
sulphuric acid  
      n   a colourless dense oily corrosive liquid produced by the reaction of sulphur trioxide with water and used in accumulators and in the manufacture of fertilizers, dyes, and explosives. Formula: H2SO4,   (Systematic name)    sulphuric(VI) acid         
sulphurous acid  
      n   an unstable acid produced when sulphur dioxide dissolves in water: used as a preservative for food and a bleaching agent. Formula: H2SO3,   (Systematic name)    sulphuric(IV) acid         
tantalic acid  
      n   a white gelatinous substance produced by hydrolysis of tantalic halides. It dissolves in strong bases to give tantalates  
tartaric acid  
      n   a colourless or white odourless crystalline water-soluble dicarboxylic acid existing in four stereoisomeric forms, the commonest being the dextrorotatory (d-) compound which is found in many fruits: used as a food additive (E334) in soft drinks, confectionery, and baking powders and in tanning and photography. Formula: HOOCCH(OH)CH(OH)COOH  
telluric acid  
      n   a white crystalline dibasic acid produced by the oxidation of tellurium by hydrogen peroxide. Formula: H6TeO6  
terebic acid  
      n   a white crystalline carboxylic acid produced by the action of nitric acid on turpentine. Formula: C7H10O4  
     (C19: from tereb(inth) + -ic)  
terephthalic acid  
      n   a white crystalline water-insoluble carboxylic acid used in making polyester resins such as Terylene; 1,4-benzenedicarboxylic acid. Formula: C6H4(COOH)2  
     (C20: from terebene + phthalic acid)  
thiocyanic acid  
      n   an unstable acid known in the form of thiocyanate salts. Formula: HSCN  
thiosulphuric acid  
      n   an unstable acid known only in solutions and in the form of its salts. Formula: H2S2O3  
thymidylic acid  
      n   a nucleotide consisting of thymine, deoxyribose, and a phosphate group. It is a constituent of DNA,   (Also called)    thymidine monophosphate  
tiglic acid  
      n   a syrupy liquid or crystalline colourless unsaturated carboxylic acid, with the trans-configuration, found in croton oil and used in perfumery; trans-2-methyl-2-butenoic acid. Formula: CH3CH:C(CH3)COOH  
     (C19 tiglic, from New Latin phrase Croton tiglium (name of the croton plant), of uncertain origin)  
titanic acid  
      n   any of various white substances regarded as hydrated forms of titanium dioxide, typical formulas being H4TiO4 and H2TiO3  
toluic acid  
      n   a white crystalline derivative of toluene existing in three isomeric forms; methylbenzoic acid. The ortho- and para- isomers are used in synthetic resins and the meta- isomer is used as an insect repellent. Formula: C6H4CH3COOH  
     (C19: from tolu(ene) + -ic)  
trans-fatty acid  
      n   a polyunsaturated fatty acid that has been converted from the cis-form by hydrogenation: used in the manufacture of margarine  
tricarboxylic acid cycle  
      n     (Biochem)      another name for       Krebs cycle     (Abbrev.)    TCA cycle  
trichloroacetic acid  
      n   a corrosive deliquescent crystalline acid with a characteristic odour, used as a veterinary astringent and antiseptic. Formula: CCl3COOH         
trichlorophenoxyacetic acid  
      n   an insoluble crystalline solid; 2,4,5-trichlorophenoxyacetic acid. It is a plant hormone and is used as a weedkiller. Formula: C8H5Cl3O3,   (Also called)    2,4,5-T  
tungstic acid  
      n   any of various oxyacids of tungsten obtained by neutralizing alkaline solutions of tungstates. They are often polymeric substances, typical examples being H2WO4 (orthotungstic acid), H2W4O13 (metatungstic acid), and H10W12O14 (paratungstic acid)  
uric acid  
      n   a white odourless tasteless crystalline product of protein metabolism, present in the blood and urine; 2,6,8-trihydroxypurine. Formula: C5H4N4O3  
uridylic acid  
      n   a nucleotide consisting of uracil, ribose, and a phosphate group. It is a constituent of RNA,   (Also called)    uridine monophosphate  
valeric acid  
      n      another name for        pentanoic acid         
vanadic acid  
      n   any one of various oxyacids of vanadium, such as H3VO4 (orthovanadic acid), HVO4 (metavanadic acid), and H4V2O7 (pyrovanadic acid), known chiefly in the form of their vanadate salts  
xanthic acid  
      n   any of a class of organic sulphur-containing acids with the general formula ROC(S)SH, where R is an organic group. Their salts are the xanthates  

Dictionnaire anglais Collins English definition-Thesaurus  

Collins
Acid House   , Acid         
      n   a type of funk-based electronically edited disco music of the late 1980s, which has hypnotic sound effects and is associated with hippy culture and the use of the drug ecstasy  
     (C20: perhaps from acid (LSD) + House (music))  


abietic acid  
      n   a yellowish powder occurring naturally as a constituent of rosin and used in lacquers, varnishes, and soap. Formula: C19H29COOH; melting pt.: 173°C  
     (C19 abietic, from Latin abiet-, from abies silver fir (the acid originally being extracted from the resin))  
acetic acid  
      n   a colourless pungent liquid, miscible with water, widely used in the manufacture of acetic anhydride, vinyl acetate, plastics, pharmaceuticals, dyes, etc. Formula: CH3COOH,   (Systematic name)    ethanoic acid      See also       glacial acetic acid       vinegar  
acetylsalicylic acid  
      n      the chemical name for       aspirin  
acid  
      n  
1    any substance that dissociates in water to yield a sour corrosive solution containing hydrogen ions, having a pH of less than 7, and turning litmus red  
   See also       Lewis acid  
2    a sour-tasting substance  
3       a slang name for       LSD  
      adj  
4      (Chem)  
a    of, derived from, or containing acid  
an acid radical     
b    being or having the properties of an acid  
sodium bicarbonate is an acid salt     
5    sharp or sour in taste  
6    cutting, sharp, or hurtful in speech, manner, etc.; vitriolic; caustic  
7    (of rain, snow, etc.) containing pollutant acids in solution  
8    (of igneous rocks) having a silica content of more than two thirds the total and containing at least one tenth quartz  
9      (Metallurgy)   of or made by a process in which the furnace or converter is lined with an acid material  
acid steel     
     (C17 (first used by Francis Bacon): from French acide or Latin acidus, from acere to be sour or sharp)  
  acidly      adv  
  acidness      n  
  acidy      adj  
acid anhydride  
      n      another name for       anhydride       3  
acid drop  
      n   a boiled sweet with a sharp taste  
acid dye  
      n   a dye in which the chromophore is part of a negative ion usually applied from an acidic solution  
acid-fast  
      adj   (of bacteria and tissues) resistant to decolorization by mineral acids after staining  
acid-forming  
      adj  
1    (of an oxide or element) yielding an acid when dissolved in water or having an oxide that forms an acid in water; acidic  
2    (of foods) producing an acid residue following digestion  
acid halide  
      n      another name for       acyl halide  
acid rain  
      n   rain that contains a high concentration of pollutants, chiefly sulphur dioxide and nitrogen oxide, released into the atmosphere by the burning of fossil fuels such as coal or oil  
acid rock  
      n   a type of rock music characterized by electronically amplified bizarre instrumental effects  
     (C20: from acid (sense 3), alluding to its supposed inspiration by drug-induced states of consciousness)  
acid salt  
      n     (Chem)   a salt formed by partial replacement of the acidic hydrogen atoms of the parent acid  
acid soil  
      n   a soil that gives a pH reaction of below 7.2, found especially in cool moist areas where soluble bases are leached away  
acid test  
      n   a rigorous and conclusive test to establish worth or value  
the play passed the critic's acid test     
     (C19: from the testing of gold with nitric acid)  
acid value  
      n   the number of milligrams of potassium hydroxide required to neutralize the free fatty acid in one gram of a fat, oil, resin, etc.  
acrylic acid  
      n   a colourless corrosive pungent liquid, miscible with water, used in the manufacture of acrylic resins. Formula: CH2:CHCOOH,   (Systematic name)    propenoic acid  
adenylic acid  
      n   a nucleotide consisting of adenine, ribose or deoxyribose, and a phosphate group. It is a constituent of DNA or RNA,   (Also called)    adenosine monophosphate  
adipic acid  
      n   a colourless crystalline solid used in the preparation of nylon. Formula: HOOC(CH2)4COOH  
     (C19: from New Latin adiposus fat + -ic)  
alginic acid  
      n   a white or yellowish powdery polysaccharide having marked hydrophilic properties. Extracted from kelp, it is used mainly in the food and textile industries and in cosmetics and pharmaceuticals. Formula: (C6H8O6)n; molecular wt.: 32000--250000  
amino acid  
      n   any of a group of organic compounds containing one or more amino groups, -NH2, and one or more carboxyl groups, -COOH. The alpha-amino acids RCH(NH2)COOH (where R is either hydrogen or an organic group) are the component molecules of proteins; some can be synthesized in the body (nonessential amino acids) and others cannot and are thus essential components of the diet (essential amino acids)  
amino acid sequence  
      n   the unique sequence of amino acids that characterizes a given protein  
aminobenzoic acid  
      n   a derivative of benzoic acid existing in three isomeric forms, the para- form being used in the manufacture of dyes and sunburn preventatives. Formula: NH2C6H4COOH  
arachidonic acid  
      n   a fatty acid occurring in animal cells: the metabolic precursor of several groups of biologically active substances, including prostaglandins  
arsenic acid  
      n   a white poisonous soluble crystalline solid used in the manufacture of arsenates and insecticides. Formula: H3AsO4  
ascorbic acid  
      n   a white crystalline vitamin present in plants, esp. citrus fruits, tomatoes, and green vegetables. A deficiency in the diet of man leads to scurvy. Formula: C6H8O6,   (Also called)    vitamin C  
     (C20 ascorbic from a-1 + scorb(ut)ic)  
aspartic acid  
      n   a nonessential amino acid that is a component of proteins and acts as a neurotransmitter  
     (C19: from aspar(agus) + -ic)  
barbituric acid  
      n   a white crystalline solid used in the preparation of barbiturate drugs. Formula: C4H4N2O3,   (Also called)    malonylurea  
     (C19: partial translation of German Barbitursäure, perhaps from the name Barbara + uric + Säure acid)  
benzenecarboxylic acid  
      n      the systematic name for       benzoic acid  
benzoic acid  
      n   a white crystalline solid occurring in many natural resins, used in the manufacture of benzoates, plasticizers, and dyes and as a food preservative (E210). Formula: C6H5COOH,   (Systematic name)    benzenecarboxylic acid  
boric acid  
      n  
1      (Also called)    orthoboric acid     (Systematic name)    trioxoboric(III) acid   a white soluble weakly acid crystalline solid used in the manufacture of heat-resistant glass and porcelain enamels, as a fireproofing material, and as a mild antiseptic. Formula: H3BO3  
2    any other acid containing boron  
bromic acid  
      n   a colourless unstable water-soluble liquid used as an oxidizing agent in the manufacture of dyes and pharmaceuticals. Formula: HBrO3  
butenedioic acid  
      n   either of two geometrical isomers with the formula HOOCCH:CHCOOH  
   See       fumaric acid       maleic acid  
butyric acid  
      n   a carboxylic acid existing in two isomeric forms, one of which produces the smell in rancid butter. Its esters are used in flavouring. Formula: C3(CH2)2COOH  
     (C19 butyric, from Latin butyrum butter)  
capric acid  
      n      another name for       decanoic acid  
     (C19: from Latin caper goat, so named from its smell)  
caproic acid  
      n      another name for       hexanoic acid  
     (C19: caproic, from Latin caper goat, alluding to its smell)  
carbamic acid  
      n   a hypothetical compound known only in the form of carbamate salts and esters. Formula: NH2COOH  
carbolic acid  
      n      another name for       phenol   esp. when it is used as an antiseptic or disinfectant   esp. when it is used as an antiseptic or disinfectant  
     (C19: carbolic, from carbo- + -ol1 + -ic)  
carbonic acid  
      n   a weak acid formed when carbon dioxide combines with water: obtained only in aqueous solutions, never in the pure state. Formula: H2CO3  
carbonic-acid gas  
      n      another name for       carbon dioxide  
carboxylic acid  
      n   any of a class of organic acids containing the carboxyl group  
   See also       fatty acid  
Caro's acid  
      n      another name for       peroxysulphuric acid  
     (C19: named after Heinrich Caro (died 1910), German chemist)  
cerotic acid  
      n      another name (not in technical usage) for       hexacosanoic acid  
chloric acid  
      n   a strong acid with a pungent smell, known only in solution and in the form of chlorate salts. Formula: HClO3  
chloroacetic acid   , chloracetic acid  
      n  
1    a colourless crystalline soluble strong acid prepared by chlorinating acetic acid and used as an intermediate in the manufacture of many chemicals; monochloracetic acid. Formula: CH2ClCOOH  
2    either of two related compounds: dichloracetic acid, CHCl2COOH, or trichloracetic acid CCl3COOH  
chlorous acid  
      n   an unstable acid that is a strong oxidizing agent. Formula: HClO2  
cholic acid  
      n   a crystalline insoluble acid present in bile: used as an emulsifying agent and an intermediate in the synthesis of organic compounds. Formula: C24H40O5  
     (C19: from Greek kholikos; see chole-)  
chromic acid  
      n   an unstable dibasic oxidizing acid known only in solution and in the form of chromate salts. Formula: H2CrO4  
cinnamic acid  
      n   a white crystalline water-insoluble weak organic acid existing in two isomeric forms; 3-phenylpropenoic acid. The trans- form occurs naturally and its esters are used in perfumery. Formula: C6H5CH:CHCOOH  
     (C19: from cinnam(on) + -ic; from its being found in cinnamon oil)  
citric acid  
      n   a water-soluble weak tribasic acid found in many fruits, esp. citrus fruits, and used in pharmaceuticals and as a flavouring (E330). It is extracted from citrus fruits or made by fermenting molasses and is an intermediate in carbohydrate metabolism. Formula: CH2(COOH)C(OH)(COOH)CH2COOH  
citric acid cycle  
      n      another name for       Krebs cycle  
crassulacean acid metabolism  
      n      the full name for       CAM       2  
crotonic acid  
      n   a colourless crystalline insoluble unsaturated carboxylic acid produced by oxidation of crotonaldehyde and used in organic synthesis; trans-2-butenoic acid. Formula: CH3CH:CHCOOH  
cyanic acid  
      n   a colourless poisonous volatile liquid acid that hydrolyses readily to ammonia and carbon dioxide. Formula: HOCN  
   Compare       isocyanic acid       fulminic acid  
cytidylic acid  
      n   a nucleotide consisting of cytosine, ribose or deoxyribose, and a phosphate group. It is a constituent of DNA or RNA,   (Also called)    cytidine monophosphate  
decanedioic acid  
      n   a white crystalline carboxylic acid obtained by heating castor oil with sodium hydroxide, used in the manufacture of polyester resins and rubbers and plasticizers. Formula: HOOC(CH2)8COOH,   (Also called)    sebacic acid  
decanoic acid  
      n   a white crystalline insoluble carboxylic acid with an unpleasant odour, used in perfumes and for making fruit flavours. Formula: C9H19COOH,   (Also called)    capric acid  
deoxyribonucleic acid   , desoxyribonucleic acid  
      n      the full name for       DNA  
dicarboxylic acid  
      n   any carboxylic acid that contains two carboxyl groups per molecule  
dichromic acid  
      n   an unstable dibasic oxidizing acid known only in solution and in the form of dichromate salts. Formula: H2Cr2O7  
disulphuric acid  
      n      another name for       pyrosulphuric acid  
dithionous acid  
      n   an unstable dibasic acid known only in solution and in the form of dithionite salts. It is a powerful reducing agent. Formula: H2S2O4,   (Also called)    hyposulphurous acid, hydrosulphurous acid  
     (from di-1 + thion-, from Greek theion sulphur + -ous)  
dodecanoic acid  
      n   a crystalline fatty acid found as glycerides in many vegetable oils: used in making soaps, insecticides, and synthetic resins. Formula: CH3(CH2)10COOH,   (Also called)    lauric acid  
     (C20: from dodecane (see dodeca-, -ane))  
erucic acid  
      adj  
      n   a crystalline fatty acid derived from the oils of rapeseed, mustard seed, and wallflower seed  
ethanedioic acid  
      n      the technical name for       oxalic acid  
     (C20: from ethane + di-1 + -o- + -ic)  
ethanoic acid  
      n      the modern name for       acetic acid  
fatty acid  
      n  
1    any of a class of aliphatic carboxylic acids, such as palmitic acid, stearic acid, and oleic acid, that form part of a lipid molecule  
2       another name for       carboxylic acid   esp. a naturally occurring one   esp. a naturally occurring one  
ferricyanic acid  
      n   a brown soluble unstable solid tribasic acid, usually known in the form of ferricyanide salts. Formula: H3Fe(CN)6  
ferrocyanic acid  
      n   a white volatile unstable solid tetrabasic acid, usually known in the form of ferrocyanide salts. Formula: H4Fe(CN)6  
folic acid  
      n   any of a group of vitamins of the B complex, including pteroylglutamic acid and its derivatives: used in the treatment of megaloblastic anaemia,   (Also called)    folacin  
     (C20: from Latin folium leaf; so called because it may be obtained from green leaves)  
formic acid  
      n   a colourless corrosive liquid carboxylic acid found in some insects, esp. ants, and many plants: used in dyeing textiles and the manufacture of insecticides and refrigerants. Formula: HCOOH,   (Systematic name)    methanoic acid  
fulminic acid  
      n   an unstable volatile acid known only in solution and in the form of its salts and esters. Formula: HONC  
   Compare       cyanic acid  
     (C19: from Latin fulmen lightning)  
fumaric acid  
      n   a colourless crystalline acid with a fruity taste, found in some plants and manufactured from benzene; trans-butenedioic acid: used esp. in synthetic resins. Formula: HCOOCH:CHCOOH  
     (C19: from New Latin Fumaria name of genus, from Late Latin: fumitory, from Latin fumus smoke)  
fuming sulphuric acid  
      n   a mixture of pyrosulphuric acid, H2S2O7, and other condensed acids, made by dissolving sulphur trioxide in concentrated sulphuric acid,   (Also called)    oleum, Nordhausen acid  
gallic acid  
      n   a colourless crystalline compound obtained from tannin: used as a tanning agent and in making inks, paper, and pyrogallol; 3,4,5-trihydroxybenzoic acid. Formula: C6H2(OH)3COOH  
gamma-aminobutyric acid  
      n      the full name for       GABA  
gibberellic acid  
      n   a slightly soluble crystalline plant hormone first isolated from the fungus Gibberella fujikuroi: a giberellin. Formula: C19H22O6  
     (C20: from New Latin Gibberella, literally: a little hump, from Latin gibber hump + -ic)  
glacial acetic acid  
      n   pure acetic acid (more than 99.8 per cent)  
glutamic acid   , glutaminic acid  
      n   a nonessential amino acid, occurring in proteins, that acts as a neurotransmitter and plays a part in nitrogen metabolism  
glyceric acid  
      n   a viscous liquid carboxylic acid produced by the oxidation of glycerol; 2,3-dihydroxypropanoic acid. Formula: C3H6O4  
glycolic acid  
      n   a colourless crystalline soluble hygroscopic compound found in sugar cane and sugar beet: used in tanning and in the manufacture of pharmaceuticals, pesticides, adhesives, and plasticizers; hydroxyacetic acid. Formula: CH2(OH)COOH  
guanylic acid  
      n   a nucleotide consisting of guanine, ribose or deoxyribose, and a phosphate group. It is a constituent of DNA or RNA,   (Also called)    guanosine monophosphate  
heptadecanoic acid  
      n   a colourless crystalline water-insoluble carboxylic acid used in organic synthesis. Formula: CH3(CH2)15COOH,   (Also called)    margaric acid  
hexacosanoic acid  
      n   a white insoluble odourless wax present in beeswax, carnauba, and Chinese wax. Formula: CH3(CH2)24COOH,   (Also called)    cerotic acid  
hexadecanoic acid  
      n      the systematic name for       palmitic acid  
hexanoic acid  
      n   an insoluble oily carboxylic acid found in coconut and palm oils and in milk. Formula: C5H11COOH  
     (C20: from hexane + -oic)  
hippuric acid  
      n   a crystalline solid excreted in the urine of mammals. Formula: C9H9NO3  
hyaluronic acid  
      n   a viscous polysaccharide with important lubricating properties, present, for example, in the synovial fluid in joints  
     (C20: hyalo- + Greek ouron urine + -ic)  
  hyaluronic      adj  
hydnocarpic acid  
      n   a cyclic fatty acid occurring in the form of its glycerides in chaulmoogra oil. Formula: C16H28O2  
     (C20: from Greek hudnon truffle + karpos fruit + -ic)  
hydrazoic acid  
      n   a colourless highly explosive liquid. Formula: HN3  
   See also       azide  
hydriodic acid  
      n   the colourless or pale yellow aqueous solution of hydrogen iodide: a strong acid  
     (C19: from hydro- + iodic)  
hydrobromic acid  
      n   the colourless or faintly yellow aqueous solution of hydrogen bromide: a strong acid  
hydrochloric acid  
      n   the colourless or slightly yellow aqueous solution of hydrogen chloride: a strong acid used in many industrial and laboratory processes,   (Formerly called)    muriatic acid  
hydrocyanic acid  
      n      another name for       hydrogen cyanide   esp. when in aqueous solution   esp. when in aqueous solution  
hydrofluoric acid  
      n   the colourless aqueous solution of hydrogen fluoride: a strong acid that attacks glass  
hydrosulphurous acid  
      n      another name (not in technical usage) for       dithionous acid  
hydroxy acid  
      n  
1    any acid, such as sulphuric acid, containing hydroxyl groups in its molecules  
2    any of a class of carboxylic acids that contain both a hydroxyl group and a carboxyl group in their molecules  
hypochlorous acid  
      n   an unstable acid known only in solution and in the form of its salts, formed when chlorine dissolves in water: a strong oxidizing and bleaching agent. Formula: HOCl  
hyponitrous acid  
      n   a white soluble unstable crystalline acid: an oxidizing and reducing agent. Formula: H2N2O2  
hypophosphoric acid  
      n   a crystalline odourless deliquescent solid: a tetrabasic acid produced by the slow oxidation of phosphorus in moist air. Formula: H4P2O6  
hypophosphorous acid  
      n   a colourless or yellowish oily liquid or white deliquescent solid: a monobasic acid and a reducing agent. Formula: H3PO2  
hyposulphurous acid  
      n      another name for       dithionous acid  
indoleacetic acid  
      n   an auxin that causes elongation of the cells of plant stems. Formula: C10H9NO2,   (Abbrev.)    IAA  
indolebutyric acid  
      n   a synthetic auxin used for stimulating plant growth and root formation. Formula: C8H6N(CH2)3COOH  
iodic acid  
      n   a colourless or pale yellow soluble crystalline substance that forms acidic aqueous solutions. Used as a reagent and disinfectant. Formula: HIO3  
isocyanic acid  
      n   a hypothetical acid known only in the form of its compounds. Formula: HNCO  
itaconic acid  
      n   a white colourless crystalline carboxylic acid obtained by the fermentation of carbohydrates and used in the manufacture of synthetic resins. Formula: CH2:C(COOH)CH2COOH  
lactic acid  
      n   a colourless syrupy carboxylic acid found in sour milk and many fruits and used as a preservative (E270) for foodstuffs, such as soft margarine, and for making pharmaceuticals and adhesives. Formula: CH3CH(OH)COOH,   (Systematic name)    2-hydroxypropanoic acid  
lauric acid  
      n      another name for       dodecanoic acid  
     (C19: from Latin laurus laurel; from its occurrence in the berries of the laurel (Laurus nobilis))  
Lewis acid  
      n   a substance capable of accepting a pair of electrons from a base to form a covalent bond  
   Compare       Lewis base  
     (C20: named after G. N. Lewis (1875--1946), US chemist)  
linoleic acid  
      n   a colourless oily essential fatty acid found in many natural oils, such as linseed: used in the manufacture of soaps, emulsifiers, and driers. Formula: C18H32O2  
     (C19: from Latin linum flax + oleic acid; so named because it is found in linseed oil)  
linolenic acid  
      n   a colourless unsaturated essential fatty acid found in drying oils, such as linseed oil, and used in making paints and synthetic resins; 9,12,15-octadecatrienoic acid. Formula: C18H30O2  
lipoic acid  
      n     (Biochem)   a sulphur-containing fatty acid, regarded as an element of the vitamin B complex, minute amounts of which are required for carbohydrate metabolism  
lysergic acid  
      n   a crystalline compound with a polycyclic molecular structure: used in medical research. Formula C16H16N2O2  
     (C20: from (hydro)lys(is) + erg(ot) + -ic)  
lysergic acid diethylamide  
      n      See       LSD  
maleic acid  
      n   a colourless soluble crystalline substance used to synthesize other compounds. Formula: HOOCCH:CHCOOH,   (Systematic name)    cis-butanedioic acid  
     (C19: from French maléique, altered form of malique; see malic acid)  
malic acid  
      n   a colourless crystalline compound occurring in apples and other fruits. Formula: HOOCCH2CH(OH)COOH  
     (C18 malic, via French malique from Latin malum apple)  
malonic acid  
      n      another name for       propanedioic acid  
     (C19: from French malonique, altered form of malique; see malic acid)  
manganic acid  
      n   a hypothetical dibasic acid known only in solution and in the form of manganate salts. Formula: H2MnO4  
margaric acid  
      n      another name for       heptadecanoic acid  
metaphosphoric acid  
      n   a glassy deliquescent highly polymeric solid, used as a dehydrating agent. Formula: (HPO3)x  
   See also       polyphosphoric acid  
methacrylic acid  
      n   a colourless crystalline water-soluble substance used in the manufacture of acrylic resins; 2-methylpropenoic acid. Formula: CH2:C(CH3)COOH  
methanoic acid  
      n      the systematic name for       formic acid  
mucic acid  
      n   a colourless crystalline solid carboxylic acid found in milk sugar and used in the manufacture of pyrrole. Formula: C4H4(OH)4(COOH)2  
     (C19: mucic, from French mucique; see mucus, -ic)  
muriatic acid  
      n      a former name for       hydrochloric acid  
     (C17: from Latin muriaticus pickled, from muria brine)  
nicotinic acid  
      n   a vitamin of the B complex that occurs in milk, liver, yeast, etc. Lack of it in the diet leads to the disease pellagra. Formula: (C5H4N)COOH,   (Also called)    niacin  
nitric acid  
      n   a colourless or yellowish fuming corrosive liquid usually used in aqueous solution. It is an oxidizing agent and a strong monobasic acid: important in the manufacture of fertilizers, explosives, and many other chemicals. Formula: HNO3,   (Former name)    aqua fortis  
nitrohydrochloric acid  
      n      another name for       aqua regia  
nitrous acid  
      n   a weak monobasic acid known only in solution and in the form of nitrite salts. Formula: HNO2,   (Systematic name)    dioxonitric(III) acid  
nonanoic acid  
      n   a colourless oily fatty acid with a rancid odour: used in making pharmaceuticals, lacquers, and plastics. Formula: CH3(CH2)7COOH,   (Also called)    pelargonic acid  
     (C19: from nonane a paraffin, ninth in the methane series, from Latin nonus ninth + -ane)  
nucleic acid  
      n     (Biochem)   any of a group of complex compounds with a high molecular weight that are vital constituents of all living cells  
   See also       RNA       DNA  
octanedioic acid  
      n   a colourless crystalline dicarboxylic acid found in suberin and castor oil and used in the manufacture of synthetic resins. Formula: HOOC(CH2)6COOH,   (Also called)    suberic acid  
     (C20: from octane + diol)  
oleic acid  
      n   a colourless oily liquid unsaturated acid occurring, as the glyceride, in almost all natural fats used in making soaps, ointments, cosmetics, and lubricating oils. Formula: CH3(CH2)7CH:CH(CH2)7COOH,   (Systematic name)    cis-9-octadecenoic acid  
     (C19 oleic, from Latin oleum oil + -ic)  
orthoboric acid  
      n      the more formal name for       boric acid       1  
orthophosphoric acid  
      n   a colourless soluble solid tribasic acid used in the manufacture of fertilizers and soaps. Formula: H3PO4,   (Also called)    phosphoric acid  
orthophosphorous acid  
      n   a white or yellowish hygroscopic crystalline dibasic acid. Formula: H3PO3,   (Also called)    phosphorous acid  
oxalic acid  
      n   a colourless poisonous crystalline dicarboxylic acid found in many plants: used as a bleach and a cleansing agent for metals. Formula: (COOH)2,   (Systematic name)    ethanedioic acid  
     (C18: from French oxalique, from Latin oxalis garden sorrel; see oxalis)  
oxo acid  
      n      another name for       oxyacid  
oxygen acid  
      n      another name for       oxyacid  
palmitic acid  
      n   a white crystalline solid that is a saturated fatty acid: used in the manufacture of soap and candles. Formula: (C15H31)COOH,   (Systematic name)    hexadecanoic acid  
     (C19: from French palmitique; see palm2, -ite2, -ic)  
pantothenic acid  
      n   an oily acid that is a vitamin of the B complex: occurs widely in animal and vegetable foods and is essential for cell growth. Formula: C19H17NO5  
     (C20: from Greek pantothen from every side)  
para-aminobenzoic acid  
      n     (Biochem)   an acid present in yeast and liver: used in the manufacture of dyes and pharmaceuticals. Formula: C6H4(NH2)COOH  
pectic acid  
      n   a complex acid containing arabinose and galactose that occurs in ripe fruit, beets, and other vegetables. Formula: C35H50O33  
pelargonic acid  
      n      another name for       nonanoic acid  
     (C19: so named because it was originally derived from pelargonium leaves)  
pentanoic acid  
      n   a colourless liquid carboxylic acid with an unpleasant odour, used in making perfumes, flavourings, and pharmaceuticals. Formula: CH3(CH2)3COOH,   (Also called)    valeric acid  
     (from pentane)  
perchloric acid  
      n   a colourless syrupy oxyacid of chlorine containing a greater proportion of oxygen than chloric acid. It is a powerful oxidizing agent and is used as a laboratory reagent. Formula: HClO4,   (Systematic name)    chloric(VII) acid  
periodic acid  
      n   any of various oxyacids of iodine containing a greater proportion of oxygen than iodic acid and differing from each other in water content, esp. either of the crystalline compounds HIO4 (metaperiodic acid) and H5IO6 (paraperiodic acid)  
     (C19: from per- + iodic)  
permanganic acid  
      n   a monobasic acid known only in solution and in the form of permanganate salts. Formula: HMnO4,   (Systematic name)    manganic(VII) acid  
peroxysulphuric acid  
      n   a white hygroscopic crystalline unstable oxidizing acid. Formula: H2SO5,   (Also called (not in technical usage))    persulphuric acid, Caros acid  
persulphuric acid   ,   (U.S.)   persulfuric acid  
      n      other names (not in technical usage) for       peroxysulphuric acid  
phosphonic acid  
      n      the systematic name for       phosphorous acid  
phosphoric acid  
      n  
1    a colourless solid tribasic acid used in the manufacture of fertilizers and soap. Formula: H3PO4,   (Systematic name)    phosphoric(V) acid     (Also called)    orthophosphoric acid  
2    any oxyacid of phosphorus produced by reaction between phosphorus pentoxide and water  
   See also       metaphosphoric acid       pyrophosphoric acid       hypophosphoric acid  
phosphorous acid  
      n  
1    a white or yellowish hygroscopic crystalline dibasic acid. Formula: H3PO3,   (Systematic name)    phosphoric acid     (Also called)    orthophosphorous acid  
2    any oxyacid of phosphorus containing less oxygen than the corresponding phosphoric acid  
phthalic acid  
      n   a soluble colourless crystalline acid used in the synthesis of dyes and perfumes; 1,2-benzenedicarboxylic acid. Formula: C6H4(COOH)2  
     (C19 phthalic, from phthal- (see phthalein) + -ic)  
picric acid  
      n   a toxic sparingly soluble crystalline yellow acid used as a dye, antiseptic, and explosive. Formula: C6H2OH(NO2)3,   (Systematic name)    2,4,6-trinitrophenol      See also       lyddite  
platinocyanic acid  
      n   a hypothetical tetrabasic acid known only in the form of platinocyanide salts. Formula: H2Pt(CN)4  
polycarboxylic acid  
      n   a type of carboxylic acid containing two or more carboxyl groups  
polyphosphoric acid  
      n  
1    any one of a series of oxyacids of phosphorus with the general formula Hn+2PnO3n+1. The first member is pyrophosphoric acid (n = 2) and the series includes the highly polymeric metaphosphoric acid. The higher acids exist in an equilibrium mixture  
2    a glassy or liquid mixture of orthophosphoric and polyphosphoric acids: used industrially as a dehydrating agent, catalyst, and oxidizing agent  
propanedioic acid  
      n   a colourless crystalline compound occurring in sugar beet. Formula: C3H4O4,CH2(COOH)2,   (Also called)    malonic acid  
     (C20: from propane + di-1 + -o- + -ic)  
propanoic acid  
      n   a colourless liquid carboxylic acid used in inhibiting the growth of moulds in bread. Formula: CH3CH2COOH,   (Former name)    propionic acid  
     (C20: from propane + -o- + -ic)  
propionic acid  
      n      the former name for       propanoic acid  
     (C19: from Greek pro- first + pionic from pion fat, because it is first in order of the fatty acids)  
prussic acid  
      n   the weakly acidic extremely poisonous aqueous solution of hydrogen cyanide  
     (C18: from French acide prussique Prussian acid, so called because obtained from Prussian blue)  
pyroligneous acid  
      n   the crude reddish-brown acidic liquid obtained by the distillation of wood and containing acetic acid, methanol, and acetone,   (Also called)    wood vinegar  
pyrophosphoric acid  
      n   a crystalline soluble solid acid formed by the reaction between one molecule of phosphorus pentoxide and two water molecules. Formula: H4P2O7  
   See also       polyphosphoric acid  
pyrosulphuric acid  
      n   a fuming liquid acid made by adding sulphur trioxide to concentrated sulphuric acid. Formula: H2S2O7,   (Also called)    disulphuric acid      See also       fuming sulphuric acid  
pyruvic acid  
      n   a colourless pleasant-smelling liquid formed as an intermediate in the metabolism of proteins and carbohydrates, helping to release energy to the body; 2-oxopropanoic acid. Formula: CH3COCOOH  
     (C19: pyruvic from pyro- + Latin uva grape)  
quinic acid  
      n   a white crystalline soluble optically active carboxylic acid, found in cinchona bark, bilberries, coffee beans, and the leaves of certain other plants; 1,3,4,5-tetrahydroxycyclohexanecarboxylic acid. Formula: C6H7(OH)4COOH  
racemic acid  
      n   the optically inactive form of tartaric acid that is sometimes found in grape juice  
ribonucleic acid  
      n      the full name of       RNA  
     (C20: from ribo(se) + nucleic acid)  
ricinoleic acid  
      n  
1    an oily unsaturated carboxylic acid found, as the glyceride, in castor oil and used in the manufacture of soap and in finishing textiles; 12-hydroxy-9-octadecanoic acid. Formula: C18H34O3  
2    the mixture of fatty acids obtained by hydrolysing castor oil  
     (C19: from ricin + oleic acid)  
saccharic acid  
      n   a white soluble solid dicarboxylic acid obtained by the oxidation of cane sugar or starch; 2,3,4,5-tetrahydroxyhexanedioic acid. Formula: COOH(CHOH)4COOH  
salicylic acid  
      n   a white crystalline slightly water-soluble substance with a sweet taste and bitter aftertaste, used in the manufacture of aspirin, dyes, and perfumes, and as a fungicide. Formula: C6H4(OH)(COOH)  
     (C19: from salicyl (via French from Latin salix a willow + -yl) + -ic)