frigate-bird: see man-o'-war bird.

frigate, originally a long, narrow nautical vessel used on the Mediterranean, propelled by either oars or sail or both. Later, during the 18th and early 19th cent., the term was applied to a very fast, square-rigged sailing vessel carrying 24 to 44 guns on a single flush gun deck. Frigates were employed by the European naval powers in large numbers as commerce raiders and for blockade duty. In the United States before the War of 1812, Joshua Humphreys designed a number of frigates superior to any other vessels of their class in speed and armament. With the introduction of steam and steel warships in the middle of the 19th cent., frigates as a class of warship passed out of use. However, during World War II frigates were reintroduced by the British as a form of antisubmarine escort larger than a corvette and smaller than a destroyer. Destroyer-type ships called frigates are important combat vessels today; however, there is no clearcut uniform distinction between a frigate and a destroyer. Modern frigates are often armed with antisubmarine weapons and guns; many are missile-armed and some are nuclear-powered. The nuclear-powered frigate U.S.S. Truxtun, launched in 1964, was the largest destroyer-type ship ever built.

or man-o'-war bird

Any member of five species of large seabirds constituting the family Fregatidae, found worldwide along tropical and semitropical coasts and islands. About the size of a hen, frigate birds have extremely long, slender wings, which span up to about 8 ft (2.3 m), and long, deeply forked tails. Most adult males are all black; most females are marked with white below. Both sexes have a bare-skinned throat pouch, tiny feet, and a long hooked bill that is used to attack and rob other seabirds of their fish. The courting male's throat pouch becomes bright red and is inflated to the size of a person's head. Perhaps the most aerial of all birds except the swifts, frigate birds land only to sleep or tend the nest.

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Either of two different types of warships, of the 17th–19th centuries and of World War II and after. The sailing ship known as a frigate was a three-masted, fully rigged vessel, often carrying 30–40 guns in all. Smaller and faster than ships of the line, frigates served as scouts or as escorts protecting merchant convoys; they also cruised the seas as merchant raiders themselves. With the transition to steam, the term gradually gave way to cruiser. In World War II, Britain revived the term frigate to describe escort ships equipped with sonar and depth charges and used to guard convoys from submarines. In the postwar decades frigates also adopted an antiaircraft role, adding radar and surface-to-air missiles. Modern frigates may displace more than 3,000 tons (2,700 metric tons), sail at a speed of 30 knots, and carry a crew of 200.

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