A game that gay little kids will try to play with older ones where they get low on you and you'll be talking to them so they yell "whack a sack" in a high pitched voice and then uppercut you to the testicles where then you fall to the ground in a bloody heap of doom and lay there in pain for the next hour. The small little kid will then proceed to laugh and run away, or even take pictures...
Dude, Butters just came up to me at lunch played "Whack A Sack" with me...it really hurt, I'm gonna kill that kid.
by T-Math September 20, 2005
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