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.

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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 )

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Other Word Forms

• quintillionth
  noun
• quintillionth
  adjective

Etymology

Origin of quintillion

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

Example Sentences

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

From MarketWatch • Mar. 18, 2026

These exascale machines can perform a quintillion calculations per second and occupy thousands of square feet -- recalling the massive size of the earliest computers.

From Science Daily • Dec. 22, 2025

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

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

From Science Magazine • Mar. 29, 2024

These breed with great rapidity under favourable conditions: one by the end of the year will be accountable, according to Linnaeus, for the enormous number of a quintillion of its species.

From Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 10 "Echinoderma" to "Edward" by Various