Korean has lots of “normal” phonological reduplication, which is a common linguistic phenomenon in many languages, notably in micronesian and polynesian groups, for example. Opening my dictionary at random, I can locate words such as: 붉다 (bulk-da, “red”) => 붉다붉다 (bulk-da-bulk-da, “very deep red”). This is a “classic” sort of linguistic reduplication, as might be taught in Linguistics 101.
But recently, in my Korean class, I was introduced to a strange sort of reduplicative process that crosses syntactic boundaries. I tried to invent a term for it, and came up with “semantic reduplication,” but that seems to be already taken for a slightly different process. So I’m not sure what to call it – maybe something like heterosyntactic reduplication? The idea being that the word element is repeated, but under different semantic categories (in this Korean case, a verb stem gets repeated, first in a derived gerund form and then in the basic verb form). Maybe someone’s already named it, but I was unable to find anything on a cursory search.
Here are some examples, that were given in class (accusative particle -을 in parenthesis is optional).
잠(을) 자다 (jam-eul ja-da, “to sleep a sleeping”)
춤(을) 추다 (chum-eul chu-da, “to dance a dancing”)
꿈(을) 꾸다 (kkum-eul kku-da, “to dream a dreaming”)
I have no idea how “productive” this type of reduplication is, but I know that at least for those verbs with which it used, it is common – not a day after my class where I was introduced to this concept, my friend sent me a text message where he used it, in the phrase “잠잤어요” (jamjasseoyo, “[you] slept a sleeping”).
In any event, I think it’s rather interesting, linguistically. Someone could write a dissertation on it.