XK may refer to: XK (protein), a protein responsible for Kx antigen which helps determine a person's blood type XK (2015 album), by Brendan Croskerry Jaguar XK, a car series made by Jaguar Jeep Commander XK, a SUV made by Jeep Republic of Kosovo, ISO 3166-1 alpha-2 user-assigned code element XK (user assigned code) CCM Airlines (IATA airline designator XK) X-K aka X Kryptonite