Mug is a word that has undergone a number of semantic shifts, or changes in meaning, over the centuries. So much so that today one wonders what connection, if any, there is between the drinking vessel and getting robbed.
The first known use of mug in English dates to 1400 and it is used in the sense of a dry measure, in this particular case a measure of salt. Where mug comes from is not known; there are cognates in other Germanic languages, but relationship these different words have to one another is uncertain.
By the early sixteenth century mug was being used to refer to large pieces of crockery, and by the middle of the seventeenth century we see the sense that we know today of a large drinking vessel with a handle. From Charles Cotton 1664 mock epic Scarronides, based on Virgil’s Aeneid, where Dido raises a mug in a toast to Aeneas:
Up from her chair queen Dido starts,
And takes a mug, that held two quarts
Of drink, that she, with much forbearing,
Had sav’d long since for her sheep-shearing:
And thus begins, “here, Sirs, here’s to you.”
In the eighteenth century mug was being used as a slang word for a person’s face. How this sense arose is not certain, but it may be from the grotesque faces that often appeared on drinking mugs of the era. The OED records this sense from 1708, after an appearance in the humorous newspaper The British Apollo:
My Lawyer has a Desk, nine Law-books without Covers, two with Covers, a Temple-Mug, and the hopes of being a Judge.
But in this passage it’s not clear whether the Temple-Mug is a drinking vessel from either the Middle Temple or Inner Temple inn of court to which London barristers belong or a statement that the lawyer affected the countenance of a barrister; or perhaps it’s a double entendre and refers to both. In any case, the use of mug to mean face is definitely attested to by the end of the eighteenth century.
By the early nineteenth-century mug had become a slang verb in the boxing community that meant to strike an opponent in the face. And by 1864 J. C. Hotten’s Slang Dictionary recorded the verb as meaning to rob someone. So the sense transferred from the face, to striking someone in the face, to robbing someone by striking or threatening to strike them. At about the same time the noun mugger, meaning a robber, also appears.
There are various other senses of mugger. The use of the word to mean a dealer or tinker in crockery dates to 1743. Mugger is nineteenth century British schoolboy slang for a diligent student, what we might now term a nerd or grind. The name for the mugger crocodile, native to India, appears by 1844. This name is unrelated to the other mugs and muggers, coming from the Hindi magar ”crocodile."
Copyright 1997-2014, by David Wilton