Athinai vs Greek capital

Athinai and Greek capital both are nouns.

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

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

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

Other synonyms of Athinai include Athens, capital of Greece.

Athinai (noun)	Greek capital (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)