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octillion

[ok-til-yuh n]
noun, plural oc·til·lions, (as after a numeral) oc·til·lion.
  1. a cardinal number represented in the U.S. by 1 followed by 27 zeros, and in Great Britain by 1 followed by 48 zeros.
adjective
  1. amounting to one octillion in number.

Origin of octillion

1680–90; < French, equivalent to oct- oct- + -illion, as in million
Related formsoc·til·lionth, noun, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for octillion

octillion

noun
  1. (in Britain and Germany) the number represented as one followed by 48 zeros (10 48)
  2. (in the US, Canada, and France) the number represented as one followed by 27 zeros (10 27)
Derived Formsoctillionth, adjective

Word Origin for octillion

C17: from French, 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