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quintillion

American  
[kwin-til-yuhn] / kwɪnˈtɪl yən /

noun

plural

quintillions,

plural

quintillion
  1. a cardinal number represented in the U.S. by 1 followed by 18 zeros, and in Great Britain by 1 followed by 30 zeros.


adjective

  1. amounting to one quintillion in number.

quintillion British  
/ kwɪnˈtɪljən /

noun

  1. US and Canadian word: nonillion.  (in Britain, France, and Germany) the number represented as one followed by 30 zeros (10 30 )

  2. Former Brit word: trillion.  (in the US and Canada) the number represented as one followed by 18 zeros (10 18 )

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • quintillionth noun

Etymology

Origin of quintillion

1665–75; < Latin quīnt ( us ) fifth + -illion (as in million )

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

So the odds of picking a perfect bracket are nowhere near 9.2 quintillion to 1 in reality.

From MarketWatch • Mar. 18, 2026

Europe recently unveiled a rival, Jupiter, housed in western Germany, also able to perform at least one quintillion calculations per second, which is equivalent to about a million smartphones.

From Barron's • Nov. 26, 2025

They expect future calculations to be performed on ORNL's Frontier, the world's most powerful supercomputer and the first exascale system, which is able to perform more than a quintillion calculations each second.

From Science Daily • May 22, 2024

There are more than 10 quintillion insects on Earth, 200 million for every human.

From Science Magazine • Mar. 29, 2024

We're moving away from it in a straight line, and that thing is three quintillion miles away.

From Islands of Space by Campbell, John Wood