A person who has more than one million dollars, pounds, or other units of currency; someone extremely wealthy.
From 'multi-' (many, from Latin 'multus') combined with 'millionaire' (one with a million units of currency). This is a relatively modern word, becoming common only in the 20th century as fortunes grew.
The word 'multimillionaire' itself is a symptom of inflation—in 1900 being a millionaire meant extreme wealth, but by 2000 you needed to be a multimillionaire just to be considered seriously rich!
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