The definition of a mug is a heavy drinking cup that usually has a handle, or a slang term for the face or mouth.(noun)
Mug is defined as to attack someone, particularly to rob him or her, or is slang for making faces in front of the camera.(verb)
See mug in Webster's New World College Dictionary
Origin: prob. < Scand, as in Swed mugg
See mug in American Heritage Dictionary 4
Origin: Perhaps of Scandinavian origin.
Origin: Probably from mug1 (possibly in allusion to mugs decorated with grotesque faces).
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