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

Billionaire John Paulson’s long Puerto Rican nightmare just took a $48 million turn in his favor.

From The Wall Street Journal • Jun. 17, 2026

Billionaire Democrat Tom Steyer is in third place in the current ballot tally, and the odds of him overtaking Hilton appear increasingly unlikely.

From Los Angeles Times • Jun. 9, 2026

Billionaire investor Mark Cuban said last month he had sold most of his bitcoin after concluding it had failed to act as a hedge against dollar weakness and geopolitical turmoil.

From MarketWatch • Jun. 5, 2026

Billionaire X owner Musk has posted several times on his platform criticising the police response.

From BBC • Jun. 4, 2026

“I’d make a go at Little Orphan Billionaire myself, except he wouldn’t stop looking at you. Hey, speaking of which, here’s a fascinating piece of trivia: Guess who gets Pickett’s billions if he dies?”

From "Turtles All the Way Down" by John Green