Wanker's Chest Share definition Flag Slang name for an overstretched diaphragm which is caused by a sharp inhalation of breath whilst masturbating. "Doc say's i've got an overstrecthed diaphragm" "Wanker's chest you mean!" rofl Wanker's Chest by Balistic July 30, 2010 0 0 Get merch Get the Wanker's Chest mug. Buy Now — $32.95 See more merch