cactus nuts Share definition Flag When the hair on your ball-sac starts growing back several days after shaving it, usually causing itching and irritation. Adam: Why do you keep scratching your junk? Ben: I got cactus nuts dude, my sac is torn up! cactus nuts by benzo11 November 14, 2006 0 0 Get merch Get the cactus nuts mug. Buy Now — $32.95 See more merch