1. Street slang, meaning "bad".
2. To assassinate another "mo-fo".
3. Nickelwhack
1. "Man, that's whack!"
2. Tony the legitimate Sicilian businessman got whacked.
3. Hairy Canadian band.
by Schubert November 26, 2003
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an event, action, or thing which makes no sense or is contrary to a logical course of action; something entirely disagreable or undesirable; A non-sequitor;
That's whack!
by Mirak Meffit August 21, 2003
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The act of completing a task with no forethought or planning what so ever.

Normally in one tenth of the time it should take to do.
Person 1: "I need a nuclear power station safety system for tomorrow".

Person 2: "No problem, i'll 'whack it in' this afternoon".
by sup my lo November 25, 2004
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Tony, did you whack that guy yet?
by idk October 5, 2003
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a word they used around the 1950's and 1960's refering to knocking somebody the fuck out or killing 'em without using arms. Often used in the triology 'The Godfather'.

1) Clemenza: Hey the Godfather asked for a direct favour, you up for a challenge?
Soldier: I'm loyal to the family, how can I help?
Clemenza: The Corleone's want that Turk asshole working with Tattaglia whacked as soon as possible. They set up Luca Brasi and we want him dead.
by # 1 Stunna July 27, 2006
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1. To be high.
2. When someone gets killed by the mafia they get whacked.
1. "I'm whacked now."
2. "Why did they have to whack him daddy?"
"He got whacked 'coz he talked son."
by Diego August 29, 2003
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