ball sack Share definition Flag hairy, hangy; unusual, disfigured sack that hangs precariously from a male penis. usually accumulate sweat and the smell of human feces. i licked a ball sack. then i barfed. ball sack by Chrysti March 1, 2004 0 0 Get merch Get the ball sack mug. Buy Now — $32.95 See more merch