billion

noun

bil·​lion ˈbi(l)-yən How to pronounce billion (audio)
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
billion adjective
billionth adjective or noun

Did you know?

How much is a billion? It might depend on whom 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 1 followed by 12 zeros. However, the French later changed their naming conventions so that a billion became a thousand million (a 1 followed by 9 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
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.
These models often contain billions of parameters, making training both resource-intensive and time-consuming. Tarun Eldho Alias, Forbes.com, 2 July 2025 Building a new complex in Maryland would have cost billions of dollars. Ross O'Keefe, The Washington Examiner, 1 July 2025 The bill threatens to end billions of dollars in green-energy tax credits, which some say could decimate the country’s wind and solar industries. Chad De Guzman, Time, 1 July 2025 In addition to spending cuts for SNAP, the bill commits billions to border security, overhauls the federal student loan program, and ends the $7,500 credit for buying an electric car passed as part of former President Joe Biden's Inflation Reduction Act. Elena Moore, NPR, 1 July 2025 See All Example Sentences for billion

Word History

Etymology

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

First Known Use

1690, in the meaning defined at sense 1

Time Traveler
The first known use of billion was in 1690

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Cite this Entry

“Billion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/billion. Accessed 11 Jul. 2025.

Kids Definition

billion

noun
bil·​lion ˈbil-yən How to pronounce billion (audio)
1
: a number equal to 1,000 million : 1,000,000,000 see number
2
: a very large number
billion adjective
billionth adjective or noun

More from Merriam-Webster on billion

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