dhow—A small sailing vessel common in Egyptian and Arabian waters. It generally carries one or two lateen sails.
dinghy—A small open boat used as a tender for a yacht.
dock—An artificially constructed basin for the reception of vessels. It may be a wet dock, where ships lie while loading and unloading, or a dry dock, in which they are repaired after the water is pumped out.
dock yard—An enclosed area in which the work connected with the building, fitting out, or repair of ships is carried on.
drabbler—An additional strip of canvas, sometimes laced to the bottom of the “bonnet” on a square sail when the wind is light. Rarely seen nowadays, but common in the Middle Ages.
draft—The depth beneath the surface of the water of the lowest point of a ship’s keel.
dreadnaught—A modern battleship carrying heavy armour and a main battery of guns all of a very large and uniform calibre.
driver—The fore-and-aft sail on the mizzenmast of a square-rigged ship. It is sometimes called the spanker.
dry dock—An artificial basin which can be flooded in order to permit the entry of ships, and then pumped dry in order that their hulls may be examined, painted, and repaired.
dugout—A canoe or boat made from a log hollowed out and cut down until it has become a vessel capable of carrying one or more passengers.