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septillion

[ sep-til-yuhn ]
/ sɛpˈtɪl yən /
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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.
adjective
amounting to one septillion in number.
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Origin of septillion

1680–90; <French, equivalent to septseven + -illion, as in million

OTHER WORDS FROM septillion

sep·til·lionth, noun, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

British Dictionary definitions for septillion

septillion
/ (sɛpˈtɪljən) /

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

Derived forms of septillion

septillionth, adjective, noun

Word Origin for septillion

C17: from French, from sept seven + -illion, on the model of million
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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