Translation guide
A small, usually round window on a ship, aircraft, or spacecraft.
A small, round window on a ship or boat.
The standard technical term for a ship's porthole. Used in nautical contexts.
船室の舷窓から海が見えた。
I could see the sea through the porthole in the cabin.
Literally 'round window'. A more general term that can refer to any round window, including portholes. Common in everyday language.
Loanword from English. Used in some contexts, but less common than native terms. May be understood by those familiar with English nautical terms.
ポートホールから外を眺めた。
I looked outside through the porthole.
A small, round window on an airplane or spacecraft.
The general word for 'window'. In context, it is understood as the aircraft window. No specific term is needed.
Light was coming in through the ship's round window.
飛行機の窓から雲が見えた。
I saw clouds from the airplane window.
Can be used for round windows on aircraft or spacecraft, emphasizing the shape.
宇宙船の丸窓から地球が見えた。
I saw the Earth through the spacecraft's round window.