quadrillion

noun

qua·​dril·​lion kwä-ˈdril-yən How to pronounce quadrillion (audio)
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
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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The least massive stars take an enormous amount of time to burn through their fuel, living as red dwarfs and dying as white dwarfs, before fading away to black after roughly a quadrillion years pass. — Big Think, 11 Feb. 2026 Even if only about one new mutation appears in the DNA each time, that adds up to roughly ten quadrillion new mutations scattered. — William A. Haseltine, Forbes.com, 14 Apr. 2026 The rapid crushing down of this stellar core doesn't just create a body of incredible density, but also creates magnetic fields that can be 1 quadrillion times stronger than Earth's magnetosphere. — Robert Lea, Space.com, 4 Feb. 2026 That transition occurs at an extraordinarily high frequency, about 2 quadrillion – 2 * 1015 – cycles per second. — Andrei Derevianko, The Conversation, 14 Apr. 2026 See All Example Sentences for quadrillion

Word History

Etymology

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

First Known Use

circa 1690, in the meaning defined above

Time Traveler
The first known use of quadrillion was circa 1690

Rhymes for quadrillion

See All Rhymes for quadrillion

Browse Nearby Words

quadrille paper
quadrillion
quadrillionth
See all Nearby Words

Cite this Entry

“Quadrillion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/quadrillion. Accessed 7 Jul. 2026.

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Kids Definition

quadrillion

noun
qua·​dril·​lion kwä-ˈdril-yən How to pronounce quadrillion (audio)
US : a number equal to 1 followed by 15 zeros see number
also, British : a number equal to 1 followed by 24 zeros see number
Last Updated: - Updated example sentences
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