Greek capital vs Athens

Greek capital and Athens both are nouns.

Word	Noun	Adjective	Verb	Adverb
Greek capital	Yes	No	No	No
Athens	Yes	No	No	No

As nouns, Greek capital and Athens are synonyms defined as:

Greek capital and Athens: the capital and largest city of Greece; named after Athena (its patron goddess)

Other synonyms of Greek capital include Athinai, capital of Greece.

Greek capital (noun)	Athens (noun)
the capital and largest city of Greece; named after Athena (its patron goddess)	the capital and largest city of Greece; named after Athena (its patron goddess)
	a university town in northeast Georgia
	a town in southeast Ohio