mouth-breather
n.— «Conversation is also the old familiar college topics with the occasional joke, sometimes racist—these people are very comfortable together—for a guffaw. “They are all stewardesses, and she had blond hair about down to here,” says a mouth-breather, also in a standard gray.» —“South Street Singles” by Sandra Earley Newsday (N.Y.) Jan. 16, 1986. (source: Double-Tongued Dictionary)