• Megamillion

    Origin

    Concatenation of mega and million

    Full definition of megamillion

    Noun

    megamillion

    (plural megamillions)
    1. (informal) A great number of millions.

    Usage notes

    The word does not come from the SI prefix mega- but from concatenation with the informal word mega. Thus the word means "a great number of millions", not a thousand million or a million million. The noun is mainly used attributively.

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