Poopnut Share definition Flag noun- an undigested peanut that is found in ones feces; can be used as a silly or affectionate term amongst friends and family. 1. "Thanks for taking the trash out, Poopnut." 2. "Poopnut side ya head say poopnut side ya head" Poopnut by wchtx December 29, 2003 0 0 Get merch Get the Poopnut mug. Buy Now — $32.95 See more merch