One of the three great divisions of Christianity; the others are the Protestant churches and the Roman Catholic Church. The Catholic and Orthodox churches were originally united, but they parted in the eleventh century, when they differed over several points of doctrine, including the supreme authority of the pope, which Orthodox Christians reject.
Note: Orthodox church buildings are beautifully and elaborately decorated. Worshipers pay special reverence to icons, which are paintings of Jesus and the saints.
Note: The Orthodox Church is the dominant form of Christianity in much of eastern Europe and in Greece.