@yukinomi that's uncultured, as in have no class/refinement. Theoretically deculture should mean de same thing but I don't think it's proper english, I've never heard of it expressed like that at least. But it might be a thing in america?
@junior1210
Lol, that UD entry makes it sound like a grave offense or something. In reality it means nothing more than "uncultured", and is much more used to shame someone for misbehaving, rather than insulting.