One of the more interesting little sub-fields in linguistics is diachronic semantics. That’s the study of how word meanings change over time. Some of these changes are relatively easy to track. A “mouse” to a farmer in 1900 was a small rodent with unfortunate grain-pilfering proclivities. To a farmer today, it’s also one of the tools she uses to interact with her computer. The word has gained a new semantic sense without losing it’s original meaning. Sometimes, however, you have a weird little dance where a couple of words are negotiating over the same semantic space–that’s another way of saying a related group of concepts that a language groups together–and that’s where things get interesting. “Cup”, “mug” and “glass” are engaged in that little dance-off right now (at least in American English). Let’s see how they’re doing, shall we?
So “cup” is doing really well, and gaining semantic ground.
Glass: Glass, on the other hand, isn’t doing as well. I haven’t yet talked to someone who can use “glass” to refer to drinking vessels that aren’t actually made of glass including, perhaps a little oddly, clear disposable cups. On the other hand, there are some types of drinking vessels that I can only refer to as glasses. Mainly those for specific types of alcohol: wine glass, shot glass, martini glass, highball glass (though I’ve heard people referring to the glass itself just as a highball, so this might be on the way out). There are alcohol-specific pieces of glassware that don’t count as glasses though–e.g. champagne flute, brandy snifter–so it’s not a categorical distinction by any means.
“Glass” seems to be pretty stable, but if “cup” continues to become broader and broader it might find itself on the outs.
Mug: I don’t have as much observational data on this one, but there seems to be another shift going on here. “Mug” originally referred only to drinking vessels that were larger than cups (see below), and still had handles.
So, at least for me, “mug” is beginning to take over the semantic space allotted to “cup” by older speakers.
Of course, this is a very cursory, impressionistic snapshot of the current state of the semantic space. Without more robust data I’m hesitant to make concrete predictions about the ways in which these terms are negotiating their semantic space, but there’s definitely some sort of drift going on.
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Tea cup, for certain. Coffee cup, OK, but coffee mug, also for certain. The dividing line between mug and cup is, I believe, the saucer. I tend to think of a mug as not having a saucer, but a cup as having one. (‘Cup and saucer’ being a set phrase.) The only tea cups I know of that don’t have saucers are those specialized Chinese ones with the lids for containing the floating leaves that one drinks with the lid on, as a strainer, sort of. And I am not sure all that many native speakers of English would recongize them as tea cups off the bat, as they are very, very much a Chinese thing, that did not seem to come into the UK along with the tea drinking habit, the English entering the tea world along with a tea pot and strainer. I do note that in your illustration, the tea cups are a with saucer set, whereas the coffee mugs are without saucer, which, to my way of thinking, makes them mugs, versus cups, and thus accurately labelled.
Tea cup, for certain. Coffee cup, OK, but coffee mug, also for certain. The dividing line between mug and cup is, I believe, the saucer. I tend to think of a mug as not having a saucer, but a cup as having one. (‘Cup and saucer’ being a set phrase.) The only tea cups I know of that don’t have saucers are those specialized Chinese ones with the lids for containing the floating leaves that one drinks with the lid on, as a strainer, sort of. And I am not sure all that many native speakers of English would recongize them as tea cups off the bat, as they are very, very much a Chinese thing, that did not seem to come into the UK along with the tea drinking habit, the English entering the tea world along with a tea pot and strainer. I do note that in your illustration, the espresso cups are a with saucer set, whereas the coffee mugs are without saucer, which, to my way of thinking, makes them mugs, versus cups, and thus accurately labelled.
Hm, interesting that it’s the saucer that makes that distinction for you… it doesn’t really play into my personal semantic divisions at all. Then again, that could be another example of age-related semantic drift. 🙂