USS Haddock (SS-231), a Gato-class submarine, was the second submarine of the United States Navy to be named for the haddock, a small edible Atlantic fish, related to the cod. A previous submarine had been named Haddock (SS-32), but was renamed K-1 prior to her launching, so Haddock (SS-231) was the first to actually bear the name. Haddock (SS-231) was laid down at the Portsmouth Navy Yard on 31 March 1941. She was launched on 20 October 1941 (sponsored by Mrs. William H. Allen), and commissioned on 14 March 1942, Lieutenant Commander Arthur H. Taylor (Class of 1927) in command.