This type of ship was devised to counter vessels called torpedo boats, & the name originally followed "torpedo boat"
These ships, which came to be called "torpedo boat destroyers" and later... [DOC] [TLE] Destroyer - Wikipedia [PAR] In naval terminology, a destroyer is a fast, maneuverable long-endurance 
warship intended to escort larger vessels in a fleet, convoy or battle group and 
defend them against smaller powerful short-range attackers.