capital of Iceland vs Reykjavik

capital of Iceland and Reykjavik both are nouns.

Word	Noun	Adjective	Verb	Adverb
capital of Iceland	Yes	No	No	No
Reykjavik	Yes	No	No	No

As nouns, capital of Iceland and Reykjavik are synonyms defined as:

capital of Iceland and Reykjavik: the capital and chief port of Iceland on the southwestern coast of Iceland; buildings are heated by natural hot water

capital of Iceland (noun)	Reykjavik (noun)
the capital and chief port of Iceland on the southwestern coast of Iceland; buildings are heated by natural hot water	the capital and chief port of Iceland on the southwestern coast of Iceland; buildings are heated by natural hot water