When the matriarch (or gay patriarch) of a party has run out of beverage and demands that a guest refill their drink. Usually accompanied with hand gestures either pointing at the offending empty glass or waving it around. Can also be posed as a question.
Luke: Alex! Mama's dry! Get me another vodka

or

Alex: I'm getting another. Is Mama dry?
by Alex Tyler January 1, 2008
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