Doing a Karl Share definition Flag To do a Karl is to be the dirtiest kind of homosexual sexual predator, but in a cute, somewhat meaty sense. "Man, that guy is totally doing a Karl, he's touching the barman up with his beefy hands." Doing a Karl by Vonatello April 6, 2008 0 0 Get merch Get the Doing a Karl mug. Buy Now — $32.95 See more merch