Courtesy flushing Share definition Flag When some one at ones friends house flushes the toilet for every individual piece of crap to avoid clogging Boy 1: I gotta go shitBoy 2: make sure you use courtesy flushing! Courtesy flushing by likeaboss9000000 February 18, 2014 0 0 Get merch Get the Courtesy flushing mug. Buy Now — $32.95 See more merch