icky-sauce Share definition Flag n 1: any distasteful or foul matter most often in liquid form. 2: a euphemism for diarrhea. my dog, cow, just went out into the yard and ate all sorts of icky-sauce. icky-sauce by fourthfavoriteanimal February 18, 2010 0 0 Get merch Get the icky-sauce mug. Buy Now — $32.95 See more merch