Why is this a tag? Its a (several) music genre with an associated aesthetic, but that aesthetic isnt exactly well defined IRL. I could see something this fuzzy being a pool but not a tag unless there is actual music.
I would say that image is more vaporwave than most posts with that tag though.
Is there a tag for the "drop seat" or "butt flap" on jumpsuits and footie pajamas? None of the phrases I've searched for have turned up any tags, and it's visually distinct from an ass_cutout.
post #3929502 Is this still a coffee mug? Doesn't look like one and instead more like teacup with coffee in it.
I agree with you. Usually that sort of taper / curve indicates a "teacup" rather than a "coffee mug", but the differences are in all honestly fairly minute. Teacups usually have thinner material than this and most "mugs". This example is sort of halfway between the prototypes.
Whole books and scientific papers have been written about this sort of thing linguistically: (see The Boundaries of Words and Their Meanings (1973) if you're bored or particularly interested). Of relevance is this illustration the author included, where he drew variously manipulated cup-like objects to see what people would name them. Basically he was trying to quantify the somewhat obvious notion that words are pretty fuzzy as to what they refer to, and there are lots of gradients and few hard and fast fixed variables. They did the same thing with "bowl", "dish", "platter", "plate", "saucer" etc, and you get the same sort of thing. On top of that since Danbooru deals so much with translation and cross-linguistic and cross-social factors, every language defines their words, gradients, and important variables differently...
In short, for English, and Danbooru in particular, I think either "teacup" or "coffee mug" applies appropriately here. I'd probably go with teacup personally even if it's not super prototypical and happens to be holding coffee at the moment.
Looking through the posts, I see that almost every coffee mug is cylindrical while every teacup is hemispherical in shape. I think that could be a good unambiguous definition for the tags, and therefore post #3929502 should be a teacup, despite holding coffee.