Flounder Slapper Share definition Flag when you slap the outside lips of a girl's orgasm chasm with your love piston for minutes on end I gave Becky a wild flounder slapper last night, but I forgot to stop before I came now she's pregnant. Flounder Slapper by cherrisa June 9, 2019 0 0 Get merch Get the Flounder Slapper mug. Buy Now — $32.95 See more merch