Basically, it's a combination of the words ballsack and butthole. It can be used in place of either words, but doesnt have the same definitions as those words. It's used as an insult, with added emphasize on butt or asshole and ballsack. It's like calling someone a ballsack and butthole at the same time.(NOTE- symonms for butthole and ballsack can also be emphasized or used) ex.- ass-sack. Another way it's used is as a curse, like damn.
Doushe 1 - You butthole!

Doushe 2 - Oh yeah?!? Well, you're a ballsack!

You - You know what?You're both buttsacks!

Ex 2 - class, we have a test today! You - Oh buttsacks!
by 1gr8beatle April 15, 2011
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When you fuck the boys in the asshole and the anus residues stick on to your dick and you can't remove the shit specks and bloodstains. Symbol of love.
Damn I went to the house and had some buttsack with the boys. Way better than my girl. #SAFTBS
by #mynamejefe May 10, 2020
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When two guys are having sex, and the giver jams it into the recievers butt, making him look like he has a ballsack on his butt, Thus a buttsack.
Dude randy gave Edris a buttsack last night, it was pretty gross.
by William Polebiter April 7, 2008
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The skin between the buttcrack and the scrotum....
And/Or
Someone who is acting dumb or wierd
Ohh my, that guy just got kicked in the buttsack,
the person who did it must of been a real buttsack to do that
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A puss filled pouch of skin found in anus or on the buttocks of grown men, used by rodents (usually mice or rats) for nesting, burrowing, gathering, ect.
I set a mouse trap in my cousin's buttsack in an attempt to catch dinner.
by Dr. Gertrude March 1, 2011
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When a person is born with the parts to form a butt (butt cheeks) but no flesh ever properly forms in it, so that the prson doesn't have the natural roundness of a butt and are therefore forced to sit on the extension of their thighs for lack of a natural butt. Or in simpler terms- lack of butt meat.
Hold on, is that Crystals's thighs or just her vestigial buttsack that's creeping from the top of her jeans when she bends over?
by Zoraya M May 19, 2008
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org. (African-Aamerican)
When a subject is soo fat that skin between the rear of the scrotum is so fat that the two look as if they were as one.
Jason's buttsack is so clean, a family of four can eat dinner off of it.

if youre happy and you know it wash your nuts with warm, fragrent oils.
by Jason Lee is 11 inches February 22, 2006
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