torpedo boat

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A small, fast warship equipped for firing torpedoes.

from The Century Dictionary.

• noun Nautical, a boat from which a torpedo is operated; especially, a small swift steamer carrying one or more offensive torpedoes for use against an enemy's ships.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun a small, high-speed warship designed to fire torpedoes, especially in coastal waters

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun small high-speed warship designed for torpedo attacks in coastal waters