port4
Pronunciation: /pɔːt/
noun
- 1an opening in the side of a ship for boarding or loading.
- a porthole: the cabin has rectangular ports set just below sheer in each quarter
- (also gun port) an opening in the body of an aircraft or in a wall or armoured vehicle through which a gun may be fired.
- an opening for the passage of steam, liquid, or gas: loss of fuel from the exhaust port

Origin:
Old English (in the sense 'gateway'), from Latin porta 'gate'; reinforced in Middle English by Old French porte. The later sense 'opening in the side of a ship' led to the general sense 'aperture'