The Collaborative International Dictionary of English v.0.48:
Port \Port\, n. [F. porte, L. porta, akin to portus; cf. AS.
porte, fr. L. porta. See Port a harbor, and cf. Porte.]
1. A passageway; an opening or entrance to an inclosed place;
a gate; a door; a portal. [Archaic]
Him I accuse
The city ports by this hath entered. --Shak.
Form their ivory port the cherubim
Forth issuing. --Milton.
2. (Naut.) An opening in the side of a vessel; an embrasure
through which cannon may be discharged; a porthole; also,
the shutters which close such an opening.
Her ports being within sixteen inches of the water.
3. (Mach.) A passageway in a machine, through which a fluid,
as steam, water, etc., may pass, as from a valve to the
interior of the cylinder of a steam engine; an opening in
a valve seat, or valve face.
Air port, Bridle port, etc. See under Air, Bridle,
Port bar (Naut.), a bar to secure the ports of a ship in a
Port lid (Naut.), a lid or hanging for closing the
portholes of a vessel.
Steam port, & Exhaust port (Steam Engine), the ports of
the cylinder communicating with the valve or valves, for
the entrance or exit of the steam, respectively.