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

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.
This has seen both sovereigns and corporates raising billions of dollars in conventional bonds and sukuk over recent months. Melissa Hancock, Fortune, 30 June 2026 The patient becomes the integration layer for a system that has spent billions digitizing itself but has not reliably connected itself. Sachin H. Jain, Forbes.com, 1 July 2026 Another Georgia family controls billions A fifth Georgia family also made the list. Irene Wright, USA Today, 1 July 2026 Federal prosecutors in Minnesota allege billions of dollars in taxpayer money may have been lost to fraud in several high-risk programs in recent years, including childcare centers and programs for children with autism. Laura Geller, CBS News, 1 July 2026 See All Example Sentences for billion

Word History

Etymology

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

First Known Use

1801, in the meaning defined at sense 2

Time Traveler
The first known use of billion was in 1801

Browse Nearby Words

Podcast

Cite this Entry

“Billion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/billion. Accessed 7 Jul. 2026.

Kids Definition

1
: a number equal to 1,000 million : 1,000,000,000 see number
2
: a very large number
billion adjective

More from Merriam-Webster on billion

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!