qua·​dril·​lion | \ kwä-ˈdril-yən How to pronounce quadrillion (audio) \

Definition of quadrillion

US : a number equal to 1 followed by 15 zeros — see Table of Numbers also, British : a number equal to 1 followed by 24 zeros — see Table of Numbers

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Other Words from quadrillion

quadrillion adjective
quadrillionth \ kwä-​ˈdril-​yən(t)th How to pronounce quadrillion (audio) \ adjective or noun

Examples of quadrillion in a Sentence

Recent Examples on the Web Cicchetti’s p-value of one in a quadrillion puts us all to shame. Benjamin Mazer, Wired, "Republicans Are P-Hacking the Supreme Court," 11 Dec. 2020 The chance of winning all four, per the suit, was less than one in a quadrillion to the fourth power. The Editors, National Review, "Texas Unleashes an Absurd Kraken," 11 Dec. 2020 Claims about this 1 in a quadrillion chance spread widely on Facebook after the Dec. 8 lawsuit. Eric Litke, USA TODAY, "Fact check: Statistical analysis supporting pro-Trump Supreme Court case is 'ludicrous'," 11 Dec. 2020 It's been hypothesized that a piece of iron of its size could be worth about $10,000 quadrillion, more than the entire economy on our planet. Francesca Giuliani-hoffman, CNN, "Psyche, an asteroid believed to be worth $10,000 quadrillion, is observed through Hubble Telescope in new study," 31 Oct. 2020 Our bodies are equipped with an astounding repertoire of B cells capable of making up to one quadrillion different antibodies. Jeffrey M. Sturek, The Conversation, "I’m a lung doctor testing the blood from COVID-19 survivors as a treatment for the sick – a century old idea that could be a fast track to treatment," 21 Aug. 2020 To googologists, number lovers who strive to define and name ever-larger numbers, utility is not the point, and even Bryson’s 100 quadrillion is small change. Melissa Mohr, The Christian Science Monitor, "There are a zillion different names for big numbers," 4 June 2020 The new coronavirus, like any virus, is a snippet of chemical memory that will repeat itself quadrillions of times, telling the same story until it is muted by other forces. New York Times, "What Sept. 11 Taught Us About Confronting Catastrophe," 29 Mar. 2020 There are trillions, quadrillions, and so forth of longer number candidates. Caroline Delbert, Popular Mechanics, "Scientists Crack Longest, Most Complex Encryption Key Ever," 6 Dec. 2019

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

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First Known Use of quadrillion

circa 1690, in the meaning defined above

History and Etymology for quadrillion

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

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Time Traveler for quadrillion

Time Traveler

The first known use of quadrillion was circa 1690

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Statistics for quadrillion

Cite this Entry

“Quadrillion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/quadrillion. Accessed 3 Mar. 2021.

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English Language Learners Definition of quadrillion

: the number 1,000,000,000,000,000 : one thousand trillion

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