This is the 322nd most frequent Japanese word.
機関
"機関" means "institution," "organization," or "mechanism."
機関 is used here to mean 'institution', as it refers to an organization or body responsible for specific functions.
この研究を行うには、指定された機関で許可を取る必要があります。
To conduct this research, it is necessary to obtain permission from the specified institution.
機関 is used here to refer to 'public transportation systems', suggesting a collective organization or service.
公共機関を利用することは、環境に優しい選択です。
Using public transportation is an environmentally friendly choice.
機関 is used here to mean 'mechanism' or 'engine', referring to a mechanical or functional part of a device or system.