Simple Definition of billionaire

from our Learner's Dictionary

billionaire

noun

ˌbɪljəˈneɚ

plural billionaires

: a rich person who has at least a billion dollars, pounds, etc.

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“Billionaire.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/billionaire. Accessed 20 Jun. 2026.

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