a pirate or person who severs the seas, especially the Mediterranean, with a vessel armed for war, without commission from any prince or power, to plunder merchant-vessels. The word comes from the Italian corsare, of corso, or à curfibus, by reason of their courses, or excursions—The name is commonly given to the piratical cruisers of Barbary, who had their rise about the beginning of the 16th century.

A corsair is distinguished from a privateer in this, that the latter does it under a commission, and only attacks the vessels of those at war with the state whence his commission is derived. The punishment of a corsair is to be hanged, without remission; whereas privateers are to be treated as prisoners of war. All corsair vessels are good prizes.