C:=X Share definition Flag A skull with crossed bones, used by modern pirates to recognize eachother over the net. Captain_Morgan: C:=XJolly_Roger: Do what you want 'cause a pirate is free, you are a pirate! C:=X by Cpt. Morgan C:=X May 29, 2010 0 0 Get merch Get the C:=X mug. Buy Now — $32.95 See more merch