USS Grampus was a schooner in the United States Navy. She was the first U.S. Navy ship to be named for the Grampus griseus, also known as Risso's Dolphin. Grampus was built at the Washington Navy Yard under the supervision of naval constructor William Doughty, based on a design by Henry Eckford. Her keel was laid down in 1820. She was launched in early August 1821. The need to suppress piracy and to maintain ships to catch slavers led to the building of five such schooners, the largest of which was Grampus. This was the first building program undertaken by the Navy since the War of 1812.