Greek Orthodox vs Orthodox

Greek Orthodox and Orthodox both are adjectives.

Word	Noun	Adjective	Verb	Adverb
Greek Orthodox	No	Yes	No	No
Orthodox	No	Yes	No	No

As adjectives, Greek Orthodox and Orthodox are synonyms defined as:

Greek Orthodox and Orthodox: of or relating to or characteristic of the Eastern Orthodox Church

Other synonyms of Greek Orthodox include Eastern Orthodox, Russian Orthodox.

Greek Orthodox (adjective)	Orthodox (adjective)
of or relating to or characteristic of the Eastern Orthodox Church	of or pertaining to or characteristic of Judaism
	of or relating to or characteristic of the Eastern Orthodox Church