millionaire
Americannoun
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a person whose wealth amounts to a million or more in some unit of currency, as dollars.
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any very rich person.
noun
Other Word Forms
Derived Forms
Inflected Forms
Nouns
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:
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
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
That’s how Brett Krieger found his way to Rocket Lab and became the millionaire he is today.
From MarketWatch • Jun. 10, 2026
The conflict-ridden country will vote Sunday for a new president, with polls predicting a June 21 runoff between leftist Senator Ivan Cepeda and right-wing millionaire lawyer Abelardo de la Espriella.
From Barron's • May 29, 2026
Self-made millionaire Fishwick made his fortune from selling vans, and founded Burnley Savings and Loan in 2011 to give local people affordable credit.
From BBC • May 4, 2026
Even a popular New York City venue allegedly uses it to blackball people its millionaire owner considers adversaries.
From Los Angeles Times • Apr. 28, 2026
A millionaire businessman and a prominent Catholic layman, Murray framed his position in stark moral terms.
From "Big Science" by Michael Hiltzik
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.