An outlet or opening for draining water; a drain found in kitchens, bathrooms, streets, etc., often associated with overflow or clogging.
キッチンの排水口に油がたまって詰まってしまった。
Grease built up in the kitchen drain and caused a clog.
台風で排水口や側溝から水があふれた。
During the typhoon, water overflowed from drains and gutters.
浴室の排水口に髪の毛がたまっているから掃除して。
The bathroom drain has hair in it, so please clean it.