Other forms: portholes
When you get the window seat on an airplane, you'll be sitting beside a porthole, which is the name for a window on an aircraft or ship.
It might sound fun to go on an ocean cruise — but it'll cost extra to stay in a cabin with a porthole. Originally, porthole applied only to the round windows on ships, initially used for firing weapons, and later simply a way to let in light and air. Though port is a common nautical term, porthole has a different source: the French porte, or "door," which first referred to the windows' watertight covers.