Akademik

a small fast unarmored and lightly armed torpedo boat; P(atrol) T(orpedo) boat

: a high-speed 60 to 100 ft. motorboat mounting two or four torpedo tubes and antiaircraft and machine guns and equipped with depth charges and smoke-making apparatus — called also mosquito boat, PT boat

motor torpedo boat,

a small, very fast, and highly maneuverable boat, having little or no armor, equipped with torpedoes, depth charges, anti-aircraft guns, and smoke-screen equipment.