half shark Share definition Flag a cock, penis, dick, willy etc that is half aroused hence - half shark. I thought he was hot and took him home, but cos he was drunk he could only get a half shark. So i let him wack off and come on my arse. half shark by poopoohead April 25, 2006 0 0 Get merch Get the half shark mug. Buy Now — $32.95 See more merch