small, fast naval vessel ranking in size below a frigate. In the 18th and 19th centuries, corvettes were three-masted ships with square rigging similar to that of frigates and ships of the line, but they carried only about 20 guns on the top deck. Frequently serving as dispatchers among ships of a battle fleet, corvettes also escorted merchantmen and showed a nation's flag in distant parts of the world.

In the early U.S. Navy, corvettes were known as ship sloops, or sloops of war. They fought with great distinction against superior British foes in the Atlantic Ocean and on the Great Lakes during the War of 1812.

Corvettes disappeared as a class after the shift to steam power in the mid-19th century, but during World War II the Royal Navy applied the term to small antisubmarine vessels escorting convoys in the Atlantic. Modern corvettes, generally displacing from 500 to 1,000 tons and armed with missiles, torpedoes, and machine guns, perform antisubmarine, antiaircraft, and coastal-patrol duties in the world's small navies.