mug

Concise Oxford English Dictionary © 2008 Oxford University Press:
mug1

▶noun

• 1 a large cylindrical cup with a handle.

• 2 informal a person's face.

• 3 Brit. informal a stupid or gullible person.

• 4 US informal a thug.

▶verb (mugs, mugging, mugged) informal

• 1 attack and rob (someone) in a public place.

• 2 make faces before an audience or a camera.

– phrases
a mug's game informal an activity likely to be unsuccessful or dangerous.

– derivatives
mugful noun (pl. mugfuls),
mugging noun.

– origin C16: prob. of Scand. origin.

Concise Oxford English Dictionary © 2008 Oxford University Press:
mug2

▶verb (mugs, mugging, mugged) (mug something up) Brit. informal learn or study a subject quickly and intensively, especially for an exam.

– origin C19: of unknown origin.