Warship built for high speed and great cruising radius, smaller than a battleship but larger than a destroyer. The term originally meant frigates of the sailing era, used to scout for enemy fleets and raid convoys. After 1880, it was a specific type of armoured warship. By World War II, cruisers served mainly as floating bases for amphibious assaults and as protection for aircraft-carrier task forces. Today U.S. cruisers carry surface-to-air missiles vital to a fleet's air-defense screen. Nuclear propulsion has given some cruisers virtually unlimited range.