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to be out of one's head on ecstasy in Cork city, Ireland
"i'm fuckin demented, boy!" followed by horrible gnashing of teeth noises
by ros2222 May 31, 2007
1. Entirely irrational: Completely unreasonable or lacking any sense of the consequences of actions taken.

2. Affected with dementia: Affected by the loss of intellectual functions that is associated with dementia. This usually only happens to elderly (old) people.
My friend's granpa is demented, he can't remember a thing.
by Jafje March 31, 2007
Third shift at the Wal-Mart Supercenter in Goshen. See Wal-Mart Mafia
I just went to Wal-mArt and damn those bitches are demented as a motherfucker
by Dark Overlord of Third Shift Dairy September 09, 2003
Result of sever head trauma, hence, retarded.
-That damn son-a-bitch gowt hit wit dis here club 'n' now he aint say nuthin no more.
-That demented moron looks at walls more than tits
by Urban Dictionary February 27, 2005
1. Something fairly absurd which triggers illogical or unreasonable laughter.

2. The new random
After I kicked him, he turned around and proceeded to gape at me with a demented stare.
by Ruby "Cuff" Slasher May 19, 2007
A really freaky-lookin' person. Usually the person looks retarded and in space.
Your brother looks so demented.
by freakinweirdo November 20, 2004
An adjective describing someone is being posed by a demon.

A young child was possed by a demon and they had to call an exorcist.