Green’s Dictionary of Slang

shit for brains phr.

also shite for brains
[shit n. (1a)]

a phr. used to imply that somebody is very stupid; a general insult.

[UK](con. 1940s) D. MacCuish Do Not Go Gentle (1962) 145: Larko’s got shit fer brains.
[[US]J. Thompson Pop. 1280 in Four Novels (1983) 475: That stinking pile of crap you call brains!].
[US]M. Braly On the Yard (2002) 279: Doesn’t anything seep through that shit you have for brains?
[US]L. Bangs in Psychotic Reactions (1988) 7: If somebody did something stupid, we used to say, ‘Whattaya got, shit for brains?’.
[US]L. Heinemann Close Quarters (1987) 266: Has this dude ever got shit for brains.
[US]C. Hiaasen Skin Tight 252: You know what you’d find . . . Shit for brains, that’s what.
Dly Press (Newport News, VA) 3 June 4/1: Unless you have poop for brains, you don’t waste a reporter’s time.
[Ire]J. O’Connor Salesman 241: Very careless lad, the Pony. Shite for brains, Homer.
[UK]Guardian 10 Feb. 64/1: Mickey has [...] ‘shit for brains’.
[US]T. Fontana ‘Blizzard of ’01’ Oz ser. 4 ep. 13 [TV script] You got shit for brains.
[UK]N. Griffiths Stump 169: They’re all stupid thick cunts, like. Can’t fuckin read or write [...] Shit-fer-brains.
Morn. Star (Vernon, BC) 9 May 58/3: Does [...] a man who once made good movies [...] have poop for brains, agreeing to direct something that stinks so bad?