billionaire

American  

[bil-yuh-nair, bil-yuh-nair] / ˌbɪl yəˈnɛər, ˈbɪl yəˌnɛər /

noun

1. a person who has assets worth a billion or more dollars, euros, etc.

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billionaire British  

/ ˌbɪljəˈnɛə /

noun

1. a person whose assets are worth over a billion of the monetary units of his country

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Etymology

Origin of billionaire

First recorded in 1855–60, billion + -aire, on the model of millionaire

Explanation

Someone who lives in the U.S. and has money, property, and investments worth at least a billion dollars is a billionaire. Being a billionaire is dependent on a country's currency; in Europe, a net worth of a billion Euros makes someone a billionaire. There are around 2,500 Americans in this category, each possessing at least $1 billion — or a thousand million dollars. During the pandemic, U.S. billionaires increased their wealth by than $1.7 trillion dollars. The French billion was originally defined as "a million million," from bi-, "two," and million, but that was altered to "a thousand million."

Example Sentences

Jury selection is to begin Monday in a high-profile legal battle between billionaire Elon Musk and artificial intelligence startup OpenAI, which he accuses of betraying its non-profit mission.

From Barron's • Apr. 25, 2026

And, unlike at Tesla, the billionaire is expected to control SpaceX through the use of so-called supervoting shares, the people said.

From The Wall Street Journal • Apr. 23, 2026

The billionaire wore Nikes instead of dress shoes, a sartorial nod perhaps to his bid to be the outsider-fighter.

From Los Angeles Times • Apr. 23, 2026

Paramount, which is looking to transform itself into a Hollywood heavyweight, is backed by tech billionaire Larry Ellison and led by his son David.

From BBC • Apr. 23, 2026

He was a rich and famous billionaire white dude.

From "The Absolutely True Diary of a Part-Time Indian" by Sherman Alexie