Catholicos

Catholicos, plural Catholicoi, is a title used for the head of certain churches in some Eastern Christian traditions. The title implies autocephaly and in some cases is borne by the designated head of an autonomous church, in which case the holder might have other titles such as Patriarch. In other cases a catholicos heads a Particular Church and is subject to a patriarch or other church head. The word comes from ancient Greek καθολικός, pl. καθολικοί, derived from καθ' ὅλου (kath'olou, "generally") from κατά (kata, "down") and ὅλος (holos, "whole"), meaning "concerning the whole, universal, general"; it originally designated a financial or civil office in the Roman Empire. The name of the Catholic Church comes from the same word.

The Church of the East, some Oriental Orthodox, Eastern Orthodox churches, and some Eastern Catholic Churches historically use this title; for example the Armenian Apostolic Church and the Georgian Orthodox Church. In the Church of the East, the title was given to the church's head, the Patriarch of the Church of the East. While in the Syriac Orthodox Church the Catholicos of the East was given to the Maphrian, historically an office below the Syriac Orthodox Patriarch of Antioch.