Depending on context this can mean either something, or someone who is:

1) Way far out there; extremely fucked up; an idiot OR,
2) beyond greatness; supercool; the bomb; very sexy.
EXAMPLE 1
"Here comes that dumbass, Dice'n Tyson. Man, he is MADWHACK off the track!"
EXAMPLE 2
"Yo, dawg, check it out. This station's playin' some MADWHACK remix beats tonight.
by Chingo Bolamongo October 10, 2006
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