Orthodox Church
- Catholic Church (disambiguation)
- Christianity as the Roman state religion
- Eastern Christianity
- Eastern Orthodox Church
- Eastern Orthodoxy
- Greek Orthodox Church (disambiguation)
- Neo-orthodoxy
- Oriental Orthodox Churches
- Orthodox (disambiguation)
- Orthodox Catholic Church (disambiguation)
- Orthodox Communion (disambiguation)
- Orthodox Presbyterian Church
- Orthodox Presbyterian Church of New Zealand
- Orthodox calendar (disambiguation)
- Orthodoxy by country (disambiguation)
- True Orthodox church