noun, often attributive
sep·​til·​lion | \ sep-ˈtil-yən How to pronounce septillion (audio) \

Definition of septillion

US : a number equal to 1 followed by 24 zeros — see Table of Numbers also, British : a number equal to 1 followed by 42 zeros — see Table of Numbers

Examples of septillion in a Sentence

Recent Examples on the Web By comparison, the pressure inside a neutron star is in the septillions of gigapascals, so these liquid cases likely occur in nature around the universe. Caroline Delbert, Popular Mechanics, "Pressure Cooking Metals Makes Them Melt Faster," 9 Dec. 2019 The number of possible routes adds up to around 15 septillion (trillion trillion), according to Goldman Sachs, an investment bank. The Economist, "In algorithms we trustHow AI is spreading throughout the supply chain," 28 Mar. 2018

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

First Known Use of septillion

1690, in the meaning defined above

History and Etymology for septillion

French, from Latin septem + French -illion (as in million) — more at seven

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Time Traveler for septillion

Time Traveler

The first known use of septillion was in 1690

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Statistics for septillion

Cite this Entry

“Septillion.” Dictionary, Merriam-Webster, Accessed 26 Nov. 2020.

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