mouth breather may me more interchangeable with slack-jawed idiot than anything else
This from
DoubletongueDictionary definition for “mouth-breather” mouth-breather n. a stupid person; a moron, dolt, genius.
Categories: English Pejorative Slang
Editorial Note: The original definition of mouth-breather referred to a person that, due to medical problems (usually with the sinuses or nose), was forced to breath via the mouth. This leaves the jaw hanging open at most times, which has a tendency to make a person look dopey or spacey.
Citations: [1944 Lloyd Lewis @ Chicago N.Y. Times (Oct.
“Of a Capitulation in Chicago”: Billy, who has grown rich on the rivers, nevertheless approached in the manner of a mouth-breather, hat in hand, toes crossed.] 1978 Cyra McFadden N.Y. Times Mag. (Feb. 5) “Mary Shelley, Mary Shelley” p. 2: “How can we reach out to the average viewer?” You know…the middle-class mouth-breather with the camper truck and the short attention span. 1985 Allan Fotheringham Maclean’s (Can.) (June 17) “The sacking of a genuine star”: One wonders, in fact, if some nervous vice-presidents at the CBC are not looking over their shoulders at some of the mouth-breathers and wall-climbers in the new Conservative caucus who always viewed the CBC as a hive of pinkos and weirdos. [1986 Sandra Earley Newsday (N.Y.) (Jan. 16) “South Street Singles” p. 4: 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.] 1987 Mike Keefe Ten Speed Commandments (Aug. 4) p. 64: Then there are the mouth-breathers. These folks are usually slack-jawed, thick-tongued individuals who congregate around pornographic movie theaters. It is the latter method that is used in cycling. 1996 Donald E. Westlake What’s the Worst That Could Happen? (Oct. 1) p. 61: No how many breasts or royals they exposed, they would still be read only by the same four hundred thousand mouthbreathers. 1997 [Lon Stowell] Usenet: alt.revenge (Jan. 23) “Re: Need help from someone with Win95 expertise”: Whatta maroon. Not only does this submoronic mouthbreather send an illegal, obscene message in private email, he posts it here publicly, with a header showing that it was also sent privately. 2001 L. Neil Smith Lever Action: Essays on Liberty (Apr. 1) p. 301: Wellywebb and his sniveling gaggle of political mouthbreathers held a highly publicized rally on the Colorado Capitol steps.