Meaning of “orthodox” - Learner’s Dictionary

orthodox

adjective uk us /ˈɔːθədɒks/
RELIGION

keeping the traditional beliefs and customs of Judaism or some types of Christianity:

an orthodox Jewish family
the Russian/Greek Orthodox Church
IDEA

If ideas or methods are orthodox, most people think they are correct, usually because they have existed for a long time:

orthodox medicine
→ Opposite unorthodox

(Definition of “orthodox” from the Cambridge Learner’s Dictionary © Cambridge University Press)