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PT boat

noun U.S. Military.
  1. a small, fast, lightly armed, unarmored, and highly maneuverable boat used chiefly for torpedoing enemy shipping.

Origin of PT boat

1940–45; p(atrol) t(orpedo)
Also called mosquito boat, motor torpedo boat.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for pt boat

PT boat

noun
  1. patrol torpedo boat, the former US term for an MTBCompare MTB
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012