Port and starboard

For the whales, see Port and Starboard (orcas). For the hedge fund, see Starboard Value.

Schematic view of a ship's navigation lights indicating its port (red) and starboard (green) sides

Port and starboard are nautical terms for watercraft, aircraft and spacecraft, referring respectively to the left and right sides of the vessel, when aboard and facing the bow (front).

Vessels with bilateral symmetry have left and right halves which are mirror images of each other. One asymmetric feature is where access to a boat, ship, or aircraft is at the side; it is usually only on the port side (hence the name).