A phrase used to indicate that the target is about to be introduced to a whole world of pain. Specifically, you, by opening this can, are going to unleash the power of whooping (that is, in the sense of attacking and beating, not in the sense of whooping cough) upon their sorry ass.
1. Specific use:
Jerry paused in thought.
"For what you have said about my mother, my girlfriend, and the proud ancestry of my forebears," he announced, "I have every intention of opening a can of whoopass."

2. General form:
"If <offending body> continues with <offending action>, it is totally time to open a can of whoopass"
by Ben Graham October 12, 2005
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usaully meaning you're going to get your ass kicked aka you're going down aka you're gunna die etc...
your about to be served a can of whoopass
by haha No September 19, 2005
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a foot stuck up (your) ass which must be surgically removed by a medical professional a.k.a (yo' mama)
a mother knows best how to treat "a can of whoopass"
by Miralem B August 9, 2005
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a can of whoopass is something you open up on someone whom you're about to fight.
I'm gettin' ready to open up a can of whoopass on you.
by Scorpiette July 14, 2005
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something i open up on sorry losers.
something my grandmother opens up when her titties sag too low
by samdog November 10, 2004
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