I mean - nowadays it sorta is, it's been heavily relegated to sexually fetishised contexts.

But the reason a "Dirndl" is called that is, because "Dirne" is a word that used to mean just "woman" but went through a linguistic evolution to mean "prostitute" quite a while ago. Off the top of my head, I don't know of an example that happened similiarly in English, but I'd guess there's bound to be something like that there, too