noun
Refers to a mechanical device that converts energy into motion, such as a steam engine or internal combustion engine. Also used in compounds like 蒸気機関 (steam engine).
この車の機関はとても静かだ。
This car's engine is very quiet.
noun
Used for formal organizations, institutions, or bodies that carry out specific functions, such as government agencies, international bodies, or corporate organs.
国際連合は平和維持のための機関です。
The United Nations is an organization for peacekeeping.
彼は政府機関で働いている。
He works at a government agency.
noun
Refers to a structured system or set of facilities designed for a particular purpose, often in compound terms like 交通機関 (transportation system) or 金融機関 (financial institution).
この地域の交通機関はよく整備されている。
The transportation system in this area is well developed.