'mug' (verb sense 'to attack and rob' and related senses) developed in English in the late 18th century; the noun 'mug' (a drinking vessel) entered English earlier from Dutch 'mok' (meaning 'mug, tankard'), and a separate sense of 'mug' meaning 'face' or 'grimace' arose later and influenced slang uses.

'mug' (noun 'drinking vessel') came into English from Dutch 'mok' in the 17th century; the sense 'face' or 'mask/grimace' appeared by the 18th century, 'to mug' meaning 'to pull faces' developed from that, and by the late 18th century thieves' slang used 'to mug' for attacking/robbing, yielding the modern verb 'mug' and its past 'mugged'.

Initially associated with a physical object ('drinking vessel') and later with facial appearance ('face' or 'grimace'); over time additional slang senses such as 'to make faces' and 'to attack and rob' emerged and became established in modern English.