oc·​til·​lion | \ äk-ˈtil-yən How to pronounce octillion (audio) \

Definition of octillion

US : a number equal to 1 followed by 27 zeros — see Table of Numbers also, British : a number equal to 1 followed by 48 zeros — see Table of Numbers

Examples of octillion in a Sentence

Recent Examples on the Web The average human adult is comprised of approximately 7,000,000,000,000,000,000,000,000,000 (7 octillion) atoms. Scott Lafee, San Diego Union-Tribune, 5 Apr. 2022 The odds of the suspect not being Blankenship, according to this match, is 1 in 3 octillion. Kevin Grasha, Cincinnati.com, 11 Feb. 2020 To put that in perspective, an octillion is a one with 27 zeros after it. Jared Gilmour, miamiherald, 27 June 2018 The researchers used this tiny deflection to calculate that the mass of Stein 2051B is about 68 percent the mass of our sun — or 1.4 octillion tons (that's 14 followed by 26 zeros). Sarah Kaplan, Washington Post, 13 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'octillion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of octillion

1690, in the meaning defined above

History and Etymology for octillion

French, from Middle French, from oct- octa- + -illion (as in million)

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Time Traveler for octillion

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The first known use of octillion was in 1690

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Cite this Entry

“Octillion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/octillion. Accessed 1 Oct. 2022.

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