Literally, when somebody's brain has stopped functioning such that they will never regain conciousness, hence coloquially somebody who is idiotic, dumb or clueless beyond belief. Similar to "too stupid to live".
You dented my car, you braindead fuck!
by Linton July 11, 2003
Get the braindead mug.
Gory zombie horror film of extremely high calibre by Lord of the Rings' Peter Jackson and Fran Walsh. Great stuff.
Braindead is a great film, I liked the bit with the lawnmower!
by cakeandfinewine September 23, 2004
Get the braindead mug.
When you smoke so much pot through out your life that you become really stupid.

Synonym: Vegetable
Joe:Poor guy, he smoked way to much pot.
Bill:He's quite the vegetable.
Joe:Maybe we should wipe up the drool from his chin?
Bill:Naw,he is braindead,he will just keep drooling.
by Roflmfaoamp May 23, 2009
Get the braindead mug.
to fuck someone in the ears so hard that they lose braincells in the process.
Jason: Sunny, can I braindead you?
Sunny: Sure thing hun!

*30 minutes later*

Jason: You alright Sunny?
Sunny: I can bake I can bake I can bake
by the savageness April 14, 2011
Get the braindead mug.
Sentient Human: Prove male privilege exists.
Braindead Feminists: ARGAGHHAGHAGHRAGHRGGAGAAGAGHA
by APersonYouMightKnow April 23, 2019
Get the braindead mug.
A increadibly idiotic individual who hasn't a sustance for anything that is going on. He or she is stupid, retarded, mental, ignorant, annoying, funny to make fun of, or any combination of the previous terms.
by CrazyBob62 May 10, 2006
Get the Braindead mug.
A disease when you tend to do something stupidly and not realize what you are doing.
Guy ; I have braindeadism.
Girl ; I know, you keep hitting yourself.
Guy ; I AM!?
by CHINGPINGLING January 17, 2011
Get the Braindeadism mug.