orthodox

adj. (Eastern orthodox) of or consisting of the Eastern churches that form a loose federation according primacy of honor to the patriarch of Constantinople and adhering to the decisions of the first seven ecumenical councils and to the Byzantine rite

also..conforming to established doctrine especially in religion.

To add a little real life use to the word, you often hear someone say that a person's behavior or actions were/was unorthodox. It was unusual or against the norm.