quadrillion
n
1 (in Britain, France, and Germany) the number represented as one followed by 24 zeros (1024), (U.S. and Canadian word)
septillion
2 (in the U.S. and Canada) the number represented as one followed by 15 zeros (1015)
determiner
3 (preceded by a or a numeral)
a amounting to this number
a quadrillion atoms
b (as pronoun) a quadrillion (C17: from French quadrillon, from quadri- + -illion, on the model of million) ♦
quadrillionth adj
septillion
n pl , -lions, -lion
1 (in Britain, France, and Germany) the number represented as one followed by 42 zeros (1042)
2 (in the U.S. and Canada) the number represented as one followed by 24 zeros (1024), (Brit. word)
quadrillion
(C17: from French, from sept seven + -illion, on the model of million)
♦
septillionth adj, n