1 The name of the left-hand side of a vessel as viewed from aft. The name probably owes its derivation to the fact that the old-fashioned merchant ships had a loading, or lading, port on their left-hand side, and ladebord, later corrupted into larboard, was the original term for the side of the vessel across which the cargo was always carried on board. The term larboard side was changed officially to port in 1844 to avoid any confusion with starboard. However, port had been used very much earlier than 1844, and Rear Admiral Robert Fitzroy is usually credited with its introduction in the British Navy, in HMS Beagle, in 1828. Mainwaring, in his Seaman's Dictionary (1625), indicates the use of the word for helm orders some 200 years earlier, and had: ‘Port. Is a word used in conding [see con] the Ship … they will use the word steddy a-port, or steddy a-starboard.’
The theory that the word port was chosen to replace larboard because a vessel burns a red light—the colour of port wine—at night on its left-hand side is demonstrably false, as the word port was used in this connection long before ships burned navigation lights at night.
2 A harbour with facilities for berthing ships, embarkation and disembarkation of passengers, and the loading and unloading of cargo.