bromby Share definition Flag One of the greatest single acts that can be performed on the commode, it involves a woman performing oral sex on a man whilst he defecates. After a long day at the railyards, a bromby would be a great pick-me-upper before the PTA meeting. bromby by Evan August 19, 2004 0 0 Get merch Get the bromby mug. Buy Now — $32.95 See more merch