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

"I did not know that number," the billionaire Trump told the New York Post, adding "I would certainly like to be there, but I wouldn't pay it either, to be honest with you."

From Barron's • May 7, 2026

Prior to joining the Trump administration, O’Neill spent more than a decade in leadership roles at hedge funds and venture capital firms led by Peter Thiel, the billionaire conservative megadonor.

From Salon • May 7, 2026

General Rob Bonta to scrutinize potential antitrust harms that would come from billionaire David Ellison’s proposed takeover of Warner Bros.

From Los Angeles Times • May 7, 2026

The billionaire suggested that his firm’s expansion will focus on Miami after the New York City mayor criticized his $238 million home.

From The Wall Street Journal • May 6, 2026

“If I was a billionaire, I’d go to every Celtics game. And maybe I’d start following football and baseball, too.”

From "Millionaires for the Month" by Stacey McAnulty