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 quadrillionth (audio) \ adjective or noun

Examples of quadrillion in a Sentence

Recent Examples on the Web According to court documents, the chance that the DNA is not his is one in 180 quadrillion. Megan Molteni, WIRED, "Lawyers in a Murder Trial Clash Over a DNA Forensics Method," 17 June 2019 This allowed him to draw conclusions along the lines of 99% of starting values greater than 1 quadrillion eventually reach a value below 200. Quanta Magazine, "Mathematician Proves Huge Result on ‘Dangerous’ Problem," 11 Dec. 2019 Sycamore’s aim was to randomly produce strings of 1’s and 0’s, one digit for each qubit, producing 253 bit strings (that is, some 9.700199254740992 quadrillion bit strings). Neil Savage, Scientific American, "Hands-On with Google’s Quantum Computer," 24 Oct. 2019 Today, a common processor has fewer than 10 billion transistors compared to more than 80 billion neurons in a human brain, translating into more that 1 quadrillion synaptic connections. Aaron Pressman, Fortune, "Intel Gains First Big Corporate Partners for Brain Computing Push," 18 Nov. 2019 And some have magnetic fields many times stronger than the norm — quadrillions of times the strength of the sun’s magnetic field. Quanta Magazine, "The Most-Magnetic Objects in the Universe Attract New Controversy," 28 Oct. 2019 If none of the superhard materials work out, scientists can start to look for ways to get the quadrillions of diamonds buried within the Earth's surface out. David Grossman, Popular Mechanics, "What the World Needs Now Is Superhard Carbon," 10 Sep. 2019 The Kivu swarm, with its three new lineages of Ebola, may amount to about one or two quadrillion infective particles of the virus. Richard Preston, The New Yorker, "Is Ebola Evolving Into a More Deadly Virus?," 7 Aug. 2019 The supercomputer, called Summit, is capable of 148 quadrillion — one million billion — calculations per second. David Goldman, CNN, "US details new restrictions on Chinese supercomputer companies," 21 June 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

Last Updated

6 Feb 2020

Cite this Entry

“Quadrillion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/quadrillion. Accessed 29 Mar. 2020.

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How to pronounce quadrillion (audio)

English Language Learners Definition of quadrillion

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

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