Groton (grŏtˈən) [key], town (1990 pop. 45,144), New London co., SE Conn., including the borough of Groton and the village of West Mystic, on the Thames River opposite New London; settled c.1650, inc. 1705. Shipbuilding, pharmaceuticals, manufacturing, and commercial fishing are among the town's industries. The huge New London Naval Submarine Base is on the Thames; the Nautilus, the first nuclear submarine, was launched there in 1954. Groton is the site of Fort Griswold (1775), unsuccessfully defended against the British in 1781. Of interest are tours of the submarine base and a number of well-maintained colonial homes. A branch of the Univ. of Connecticut is in Groton. Silas Deane was born there.