billionaire

American  

[bil-yuh-nair, bil-yuh-nair] / ˌbɪl jəˈnɛər, ˈbɪl jəˌnɛər /

noun

billionaires plural

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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Other Word Forms

Noun Inflected Forms

• billionaires
  plural

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

A fleet of lawyers for Indian billionaire Gautam Adani pressed the Justice Department last year to drop a 2024 fraud case against the founder and chairman of energy and logistics giant Adani Group.

From The Wall Street Journal • Jun. 16, 2026

If even a high-profile billionaire global philanthropist is in the dark, what does that mean for the billions of women with less than a fraction of her resources?

From Salon • Jun. 14, 2026

Not all SpaceX promises were kept though: that same year, Musk said he would send a group which included Japanese billionaire Yusaku Maezawa around the Moon by 2023, but that never came to pass.

From Barron's • Jun. 12, 2026

At the time, Cipriani had widened his lawsuit to include Shell’s wife, Laura, and tech billionaire Larry Ellison, whose son David Ellison runs Paramount.

From Los Angeles Times • Jun. 11, 2026

“As a library reaches out to the community surrounding it,” said the bizarro billionaire, “so do the games of the first Library Olympiad!”

From "Mr. Lemoncello's Library Olympics" by Chris Grabenstein