noun, plural sep·til·lions, (as after a numeral) sep·til·lion.
a cardinal number represented in the U.S. by 1 followed by 24 zeros, and in Great Britain by 1 followed by 42 zeros.
amounting to one septillion in number.
Origin of septillion
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
noun plural -lions or -lion
(in Britain, France, and Germany) the number represented as one followed by 42 zeros (10 42)
(in the US and Canada) the number represented as one followed by 24 zeros (10 24)Brit word: quadrillion
Word Origin for septillion
C17: from French, from sept seven + -illion, on the model of million
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