Namoi River vs Commonwealth of Australia

Namoi River and Commonwealth of Australia both are nouns.

Word	Noun	Adjective	Verb	Adverb
Namoi River	Yes	No	No	No
Commonwealth of Australia	Yes	No	No	No

Namoi River (noun)	Commonwealth of Australia (noun)
a river in southeastern Australia that flows generally northwest to join the Darling River	a nation occupying the whole of the Australian continent; Aboriginal tribes are thought to have migrated from southeastern Asia 20,000 years ago; first Europeans were British convicts sent there as a penal colony