Organization of the Eastern Orthodox Church

The Eastern Orthodox Church, officially the Orthodox Catholic Church and commonly known simply as the Orthodox Church, is a communion composed of up to seventeen separate autocephalous (self-governing) hierarchical churches that profess Eastern Orthodoxy and recognise each other as canonical (regular) Eastern Orthodox Christian churches. Each constituent church is self-governing; its highest-ranking bishop (known variously as a patriarch, metropolitan or archbishop) serves as the primate and reports to no higher authority.

Source: Wikipedia — Organization of the Eastern Orthodox Church (CC BY-SA 4.0)