drain hole; scupper; osculum
Refers to an opening for draining water, such as a scupper on a ship or deck, or an osculum in sponges. The term 'osculum' is a technical biological term.
船のデッキには排水孔がいくつか設けられている。
Several scuppers are installed on the ship's deck.
海綿動物の体の表面には排水孔と呼ばれる大きな開口部がある。
On the surface of a sponge's body, there is a large opening called an osculum.