mug

Short definition from Wiktionary

Noun

1. 1
   A large cup for beverages, usually having a handle and used without a saucer.
2. 2
   The face.
3. 3
   A gullible or easily cheated person.
4. 4
   A stupid or contemptible person.
5. 5
   A criminal.
6. 6
   A mug shot.
7. 7
   Motherfucker (usually in similes, e.g. "like a mug" or "as a mug")
8. 8
   Alternative form of Magh.

Verb

1. 1
   To strike in the face.
2. 2
   To assault for the purpose of robbery.
3. 3
   To exaggerate a facial expression for communicative emphasis; to make a face, to pose, as for photographs or in a performance, in an exaggerated or affected manner.
4. 4
   To photograph for identification; to take a mug shot of.
5. 5
   To learn or review a subject as much as possible in a short time; cram.

Adjective

1. 1
   Easily fooled, gullible.
2. 2
   Uninteresting or unpleasant.