"left-hand side of a ship" (to a person on board and facing the bow), c.1300, ladde-borde, perhaps lit. "the loading side," if this was the side on which goods were loaded onto a ship, from laden "to load" + bord "ship's side." Altered 16c. on influence of starboard, then largely replaced by
port (1). to avoid confusion of similar-sounding words. The O.E. term was bæcboard, lit. "back board" (see starboard).