capital of Senegal vs national capital

capital of Senegal and national capital both are nouns.

Word	Noun	Adjective	Verb	Adverb
capital of Senegal	Yes	No	No	No
national capital	Yes	No	No	No

capital of Senegal (noun)	national capital (noun)
the capital and chief port and largest city of Senegal	the capital city of a nation