Thoonk Share definition Flag The sound it makes when a man enters a woman via anal sex really fast man, I was pushing, but she was stressing, and I stroked her back, so she relaxed, and it went THOONK! Thoonk by Mechwarrior Buddah February 13, 2017 0 0 Get merch Get the Thoonk mug. Buy Now — $32.95 See more merch