bil·lion | \ˈbi(l)-yən \

Definition of billion 

1 US : a number equal to 1,000 million — see Table of Numbers also, British : a number equal to 1,000 milliard — see Table of Numbers

2 : a very large number

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Other Words from billion

billion adjective
billionth \ˈbi(l)-yən(t)th \ adjective or noun

Did You Know?

How much is a billion? It might depend who you ask. Billion was borrowed from French in the late 1600s to indicate the number one million raised to the power of two, or a million million - a number represented by a one followed by 12 zeros. However, the French later changed their naming conventions so that a billion became a thousand million (a one followed by nine zeros) and a trillion became a thousand thousand million (or a million million, the old billion). The French have since returned to the older system, but it was this new system that was adopted by American English speakers in the 1800s. In Britain the newer system has seen increasing use since the 1950s, but the older sense is still sometimes used there as well.

Examples of billion in a Sentence

We could see a billion stars in the sky.

Recent Examples on the Web

For the technological giant that has made its billions in advertising, X isn’t a junk drawer for unusual projects that don’t fit elsewhere in the corporate structure. Alex Davies, WIRED, "Inside X, the Moonshot Factory Racing to Build the Next Google," 11 July 2018 Past research has found 1 meter of sea-level rise could cost the National Park Service billions of dollars. Adam Aton, Scientific American, "Government Sea Level Rise Report Released After Charges of Censorship," 21 May 2018 The Postal Service does lose billions each year, and has for the past decade. Jen Kirby, Vox, "Trump thinks Amazon’s destroying the post office. Here’s what’s really happening.," 30 Mar. 2018 But the penalty isn’t likely to reach into the double-digit billions range, these people said. Sam Schechner, WSJ, "Google to Face Multibillion-Euro European Union Antitrust Fine," 10 July 2018 Holmes, 34, once graced the cover of magazines and was worth billions on paper. Elizabeth Weise, azcentral, "Theranos founder Elizabeth Holmes and former president Balwani charged with federal fraud," 15 June 2018 Such entities have the billions in revenue that can be plowed into R&D of custom chips without the need for immediate and obvious return on investment. Andy Patrizio, Ars Technica, "The AI revolution has spawned a new chips arms race," 9 July 2018 The therapy involves analyzing the DNA in a sample of each patient's cancer, sifting through tumor tissue for T-cells that appear to be programmed to go after the mutations and expanding those cells by the billions in the laboratory. Todd Ackerman, Houston Chronicle, "Immunotherapy defeats a breast cancer that had defied other treatments," 5 June 2018 Protests and regulatory back-and-forth can cost companies millions, if not billions, of dollars. Katherine Blunt, San Antonio Express-News, "Building pipeline support, one chicken, lamb and goat at a time," 5 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'billion.' 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 billion

1690, in the meaning defined at sense 1

History and Etymology for billion

French, from bi- + -illion (as in million)

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Statistics for billion

Last Updated

14 Oct 2018

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Time Traveler for billion

The first known use of billion was in 1690

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English Language Learners Definition of billion

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

: a very large amount or number

: the number 1,000,000,000,000


bil·lion | \ˈbil-yən \

Kids Definition of billion

1 : a thousand millions

2 : a very large number billions of stars

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Comments on billion

What made you want to look up billion? Please tell us where you read or heard it (including the quote, if possible).


evasion of direct action or statement

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