look up any word, like cunt:
 
7.
A serious medical condition where fecal matter has replaced brain matter. Dangerous, but with low mortality rate.

Symptoms: Verbal diarrhea, poor decision making skills and acne.

Cure: There is no known cure, recommend quarantine from general populace.
Exhibit A: George W Bush - Ran up a big bill, couldn't find a WMD or Osama in 2 terms.
Exhibit B: Everyone who voted for him.
Exhibit C: Most politicians.

Usage: Your alcoholic dad has shit for brains, you are a credit to the family.
by Bushwhacked June 25, 2011
 
1.
1. Stupid. Careless.

2. A person evincing these characteristics.
1. "What a shit for brains thing to do."

2. "That shit for brains Bob left the oven on when he left for Jamaica."
by Famous Mortimer January 24, 2003
 
2.
An idiot; one who seems to have shit instead of brains, thus severely limiting their thought capacity.
Hey shit-for-brains, you fucked up again didn't you?
by progamer124 January 18, 2003
 
3.
A stupid person, does not actualy refer to anyone actualy having shit in their skull.
"God damn it, you really do have shit for brains dont ya?!"
by MattTheJackass November 01, 2005
 
4.
noun; any animal having shit substituted for brains in the region of the skull: a direct result of having ones head up ones ass
That Jim is one of the dumbest mother fuckers I know. What a fucking "shit for brains".
by green giant March 08, 2003
 
5.
It means that someone is extremely stupid that they don't have a functional brain, instead they have shit (meaning nothing) where their brain is supposed to be.
Person # 1: Where the hell is Ray?
Person # 2: I don't know, I don't think he's coming tonight.
Person # 1: He's such a fucking idiot, he's ruining it for me too, I swear he has shit for brains!"
by LILR1 July 22, 2008
 
6.
A shit for brains is usually heavily retarded, or this is this a gross understatement? My 40 year old sister thinks that electric cookers run off gas and she doesn't have a clue how much anything is at Poundland. She isn't just thick, she has shit for brains. Fancy calling your kids Skip? Toad? Soil? and Dildo? Fucking stupid shit for brains bitch Notwithstanding, she has very recently learnt to write her own name. Need I say more? She's a shit for brains. She's an ass wipe. She's a lude crude rude bag of pre chewed food, dude. She has the only house that you are more likely to slip on a turd inside, than outside in the street. Shit for brains also live in shit and furthermore never clean the toilet.
A shit for brains live in a smashed up stone henge's of a house, complete with boarded windows and big black and white checks up the walls. Gone is the stone furniture, gone is the scabies. She is a shit for brains along with her brand new silver woodwork and a purple wall. Shit for brains totally fucking ruin houses, no shit. Shit for brains live off Pot noodle, Frozen pizza, done in microwaves, check that grease and get pissed every day on anything remotely alcoholic. Shit for brains go out with or marry guys called Andy, who are also well and truly SHIT FOR BRAINS!
by Freddy fingers 45 May 02, 2012