Butt Sick Share definition Flag butt sick adj.: 1. A general feeling of frustration and/or anger. 2. Diarrhea "This project is making me butt sick." "That chilli made me butt sick." Butt Sick by flurbury September 18, 2007 0 0 Get merch Get the Butt Sick mug. Buy Now — $32.95 See more merch