Cruiser
1. From the mid-19th century to the mid-20th century, a classification for a wide variety of gun- and sometimes torpedo-armed warships, usually but not always armored, intended for independent scouting, raiding, or commerce protection; some were designed also to provide direct support to a battle fleet. Cruisers carried out functions performed previously by the cruising ships (sailing frigates and sloops-of-war) of the Age of Sail.
2. From the early to the mid-20th century, a type of armored warship with varying armament and of various sizes, but always smaller than a battleship and larger than a destroyer, capable of both direct support of a battle fleet and of independent operations, armed with guns and sometimes torpedoes.
3. After the mid-20th century, various types of warships of intermediate size armed with guided missiles and sometimes guns, intended for air defense of aircraft carriers and associated task forces or for anti-ship missile attacks against such forces; virtually indistinguishable from large destroyers since the late 20th century.
4. A yacht with one or more cabins containing the facilities for living aboard, thus capable of making voyages.