It has been outlandishly hot and muggy in Nashville lately. which got me wondering if there were any connection between that word muggy and the word mug—as in “coffee mug.” I thought maybe it had something to do with the idea that the air feels hot and soupy, like something you might drink out of a mug. That conjecture turned out to be false. But I found out some interesting things about the words mug and muggy and various words surrounding them. I thought you might find them interesting too.
Let’s start with mug, which, besides being something to drink out of, is also a term for a person’s face. Versions of the word mug—meaning “earthenware drinking vessel”—appear in various Germanic languages. Nothing too interesting there. But how do we get from that kind of mug to the slangy use of mug to mean face (see also mugshot and mugging for the camera)?
In the seventeenth century, ceramics manufacturers started making mugs and jugs in the shape of human faces. This one, in the likeness of Shakespeare’s Falstaff, holds pens and pencils in my office.
It wasn’t long before pub-goers began to notice the similarities between mugs and human faces and began to refer to their companions’ faces as mugs.
In the United States, at least, the most common use of mug to mean face is found in the compound noun mugshot, a photograph of an arrested suspect’s face taken at the the police station.
In the nineteenth century, the act of hitting someone in the face—especially in the boxing ring—came to be known as mugging. In the intervening years, the meaning broadened to cover assault more generally, then specialized back down to mean, usually, the street crime of assaulting and robbing a person.
The muggy weather around here has felt assaultive lately; stepping outside has felt like getting mugged. But that still doesn’t explain the origin of the adjective muggy.
In Middle English there was a verb mugen, meaning “to drizzle,” which gave rise to the now-obsolete noun mug, meaning fog or mist. Muggy air is so heavy it feels like a hot fog or mist.
It has been suggested that the mugen derived from the Proto Indo-European root *meug, which means “slimy or slippery.” This is the root that gave us moist and mucus–which seems just about right, since the air is approximately 98.6 degrees Fahrenheit and wet and gloopy and slippery as I write this.
Bonus mucus-related etymology
I was surprised to learn that the word match (as in kitchen match, safety match, and strike-anywhere match) is also part of the constellation of mucus-related words. Match derives from the Old French meiche, “candlewick.” Meiche derived from the Latin myxa, meaning a lamp wick, and/or the snout of the lamp from which the wick dangles.
And the Latin. myxa, it has been suggested, derived from the Greek myxa, meaning mucus, or more specifically, snot. Some imaginative Roman, it seems, thought that the wick dangling from the end of a lamp looked like snot dangling from a nose. I like to imagine this Roman as a young uncle trying to entertain his nieces and nephews, never suspecting that his puerile humor would spread around the world and down the centuries.