mug ; A vulgar characterization for the human face.

“to mug  oneself,” to get tipsy.
to strike in the face, or fight. Also, to rob or swindle. Gaelicmuig , to suffocate, oppress; Irishmugaim , to kill, destroy.

the mouth, or face.—Old.

“‘Goblet and mug.'—Topers should bear in mind that what they quaff from the goblet afterwards appears in the mug.”