Donkey-brained 

A term coined by the great Charlie Kelly meaning someone who possesses inferior intelligence and a lack of common sense, similar to a donkey, or activity that would suggest such.

Dennis eating cereal while driving was completely Donkey-brained.

Donkey-brained by TurkTurkleton June 6, 2013

Shit Brained 

Getting so Drunk that you forget most of what you did the last time you got drunk, and had shit for brains. hence Shit Brained"

"boy i got shit brained, i didnt know what the hell i was doing, i think i had sex with a postbox"

Shit Brained by the Real B-Man April 11, 2010

smooth-brained 

An insult referring to the absence of wrinkles present in the human telencephalon(cerebrum) -- the largest region of the mammalian brain. Literally implying idiocy at a physiological level.

Those smooth-brained idiots voted for G.W. Bush twice!

smooth-brained by drastic_quench May 23, 2008

Basten Brained 

Someone who is the result of 16 generations of inbreeding therefor lacks any form of intelligence, self awareness and Behaves in hot-headed and impulsive way.
Usually also sociopathic.

That guy just hit his teacher because he didnt pass his test, He's Basten Brained

Basten Brained by xMonkeyMonk August 31, 2021

braincrush 

When you have a crush on a person's brain, with complete disregard to appearance, availability, etc.

Laura has a braincrush on Thomas Jefferson.

braincrush by awesomeaardvark October 21, 2009

Flat Brained 

Flat Brained (Flatius Branium) is a common condition where the victim goes into a nearly catatonic state and shows no signs of brain activity, unable to achieve basic cognitive thought and anything above basic involuntary muscle work. Victims tend to constantly say and do utter nonsense and continue to do such until their vital organs eventually shut down.

Someone take the sandpaper away from Johnny, he's going to go flat brained again.

Flat Brained by GoldJohnnyBoi March 20, 2020

brained 

Verb. To be hit really hard in the head.

I got seriously brained against a brick wall and I still can't see straight.

brained by Fab Swing Dancer (who has been nearly brained on several occasions) May 22, 2006