The Eastern Orthodox Church, officially called the Orthodox Catholic Church, and also referred to as the Orthodox Church and Orthodoxy, is the second largest Christian church in the world, with an estimated 225–300 million adherents, primarily in Eastern and Southeastern Europe and the Middle East. It is the religious affiliation of the majority of the populations of Belarus, Bulgaria, Cyprus, Georgia, Greece, Macedonia, Moldova,Montenegro, Romania, Russia, Serbia, and Ukraine; significant minority populations exist in Jordan, Israel, Lebanon and Syria.

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