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

“It’s not going to be 9 quintillion to 1, but it will still be billions to 1.”

From MarketWatch • Mar. 18, 2026

Kader said the energy carried by the coronal gas is equivalent to 10 quintillion hydrogen bombs exploding every second.

From Science Daily • Jan. 10, 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

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

From Science Magazine • Mar. 29, 2024

Take up your table of logarithms and figure away until you are blind, and such an accident could not happen in as many thousand, billion, trillion, quintillion years as you can express by figures.

From The Works of Robert G. Ingersoll, Vol. 10 (of 12) Dresden Edition?Legal by Ingersoll, Robert Green