reflux vb
1 (Chem) to boil or be boiled in a vessel attached to a condenser, so that the vapour condenses and flows back into the vessel n
b (as modifier)
a reflux condenser
3 the act or an instance of flowing back; ebb
(C15: from Medieval Latin refluxus, from Latin refluere to flow back)
reflux oesophagitis n inflammation of the gullet caused by regurgitation of stomach acids, producing heartburn: may be associated with a hiatus hernia