Flabbajack Share definition Flag 1)A flap of skin leftover from liposuction and or losing alot weight really fast Dude did you see his flabbajack? Shes hot but i heard she has a flabbajack. Flabbajack by FLAMEBOI April 4, 2008 0 0 Get merch Get the Flabbajack mug. Buy Now — $32.95 See more merch