millionaire

American  

[mil-yuh-nair] / ˌmɪl yəˈnɛər /

Or millionnaire

noun

1. a person whose wealth amounts to a million or more in some unit of currency, as dollars.

2. any very rich person.

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millionaire British  

/ ˌmɪljəˈnɛə /

noun

1. a person whose assets are worth at least a million of the standard monetary units of his country

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Other Word Forms

• millionairedom noun
• millionairess noun
• nonmillionaire noun

Etymology

Origin of millionaire

1820–30; < French millionnaire, equivalent to million million + -aire -ary

Compare meaning

How does millionaire compare to similar and commonly confused words? Explore the most common comparisons:

• multimillionaire vs. millionaire

Explanation

A millionaire is someone who has at least a million dollars. If you're a millionaire, you are incredibly wealthy — but not as rich as a billionaire. In U.S., if you have a million dollars — or things that are worth that much, like a million-dollar house — you're a millionaire. In the U.K., a millionaire has a million pounds. This word describes a specific amount of wealth, but it's also a metaphor for "rich," so you might say, "My neighbors are millionaires — they travel to foreign countries all the time!" The first American millionaire was John Jacob Astor, who earned his riches from 18th-century fur trading.

Example Sentences

Or maybe better to cite is the old Steve Martin gag about how you can be a millionaire and never pay taxes: “First, get a million dollars.”

From The Wall Street Journal • Apr. 10, 2026

"If I had a pound for every time I said 'tuck your shirt in', I wouldn't need to teach, I'd be a millionaire," laments one Derbyshire secondary school teacher.

From BBC • Feb. 21, 2026

Uwe Jun of Trier University told AFP that Merz -- a millionaire hobby pilot -- "still struggles when it comes to public likability."

From Barron's • Feb. 20, 2026

I’ve received many letters where the case seems stronger than the one you describe; one reader wrote to say her millionaire cousin’s nursing home coerced her into changing her will and selling her house.

From MarketWatch • Jan. 7, 2026

Well, now, I’m not a millionaire, but here .

From "Angela's Ashes: A Memoir" by Frank McCourt