About three centuries ago port began to replace larboard as the word for the
left-hand side of a ship, probably because larboard was too easily confused in
speech with starboard, the right-hand side. The word port here probably derives
from port, a harbor. In the days when the steering gear was on the starboard
(that is, steer-board) side, a vessel almost always had to tie up at the dock
with her left side toward the port.