Ecumenical Patriarchate of Constantinople
The Ecumenical Patriarchate of Constantinople (Greek: Οἰκουμενικὸν Πατριαρχεῖον Κωνσταντινουπόλεως, romanized: Oikoumenikón Patriarkhíon Konstantinoupóleos) is one of the fifteen to seventeen autocephalous churches that together compose the Eastern Orthodox Church. It is headed by the Ecumenical Patriarch of Constantinople.
Source: Wikipedia — Ecumenical Patriarchate of Constantinople (CC BY-SA 4.0)