arc of shit Share definition Flag shitting through someone's letter box, so when they open the door, the poo gets smeared in an arc across their carpet. motherfucker! i came home, opened the door, and smeared an arc of shit right across my hallway arc of shit by Serge Fabrizio October 29, 2007 0 0 Get merch Get the arc of shit mug. Buy Now — $32.95 See more merch