Russian Orthodox vs Orthodox

Russian Orthodox and Orthodox both are adjectives.

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

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

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

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

Russian 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