self-governing body; autonomous organ
Refers to an organization or institution that governs itself, such as a local government, professional association, or university.
The university is operated as a self-governing body.
A local government is a type of self-governing body.
自治体 specifically refers to a local government entity, while 自治機関 is a broader term for any self-governing organization.
Compound of 自治 (self-government) and 機関 (organization, organ).