| 1. | of, pertaining to, or conforming to the approved form of any doctrine, philosophy, ideology, etc. |
| 2. | of, pertaining to, or conforming to beliefs, attitudes, or modes of conduct that are generally approved. |
| 3. | customary or conventional, as a means or method; established. |
| 4. | sound or correct in opinion or doctrine, esp. theological or religious doctrine. |
| 5. | conforming to the Christian faith as represented in the creeds of the early church. |
| 6. | (initial capital letter ) of, pertaining to, or designating the Eastern Church, esp. the Greek Orthodox Church. |
| 7. | (initial capital letter ) of, pertaining to, or characteristic of Orthodox Jews or Orthodox Judaism. |

orthodox
(from Greek orthodoxos, "of the right opinion"), true doctrine and its adherents as opposed to heterodox or heretical doctrines and their adherents. The word was first used in early 4th-century Christianity by the Greek Fathers. Because almost every Christian group believes that it holds the true faith (though not necessarily exclusively), the meaning of "orthodox" in a particular instance can be correctly determined only after examination of the context in which it appears.
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