Real Dictionary

mug
countable noun: A mug is a large deep cup with straight sides and a handle, used for hot drinks.

mug in American English
intransitive verb: to grimace; exaggerate a facial expression, as in acting
noun: a drinking cup, usually cylindrical in shape, having a handle, and often of a heavy substance, as earthenware
transitive verb: to assault or menace, esp. with the intention of robbery

mug in American English 1
a heavy drinking cup of earthenware or metal, having a handle and formerly often ornamented with a human face
to assault a person, usually with intent to rob
to assault usually with intent to rob

mug in American English 2
to study hard and hurriedly, as in preparation for an examination; cram

mug in British English 1
noun: a drinking vessel with a handle, usually cylindrical and made of earthenware

mug in British English 2
noun: a person's face or mouth