koala flaps Share definition Flag a piece of Kangaroo meat cut into the shape of "piss flaps" and then tried to be fed to the naive English Pommy "Here mate would you like to try some BBQ'd Koala flaps" koala flaps by Colonel-Briggs November 17, 2011 0 0 Get merch Get the koala flaps mug. Buy Now — $32.95 See more merch