noun
plural mugs
[count] a large drinking cup with a handle
the liquid that is contained in a mug
slang :the face or mouth of a person
Brit informal :a foolish person who is easily tricked :patsy
verb
mugs; mugged; mugging
[+ obj] :to attack and rob (someone)
[no obj] chiefly US :to act or pose in a silly way or make silly facial expressions especially to attract attention or when being photographed - usually + for
mug up
[phrasal verb]
mug up or mug (something) up or mug up (something) or mug up on (something) Brit informal :to study or try to learn a lot of information quickly for a test, exam, etc.