This type of ship was devised to counter vessels called torpedo boats, & the name originally followed "torpedo boat"
Formerly known as DD 21, the program will now be called "DD(X)" to 
more... [DOC] [TLE] Vintage Metal Steel Battleship 16" Model SHIP Destroyer ... - eBay [PAR] They were originally developed in the late 19th century as a defence against 
torpedo boats, ... [2] Before World War II, destroyers were light vessels with little 
endurance for ... Fast boats armed with torpedoes were built and called torpedo 
boats.