Simpson Desert vs Commonwealth of Australia

Simpson Desert and Commonwealth of Australia both are nouns.

Word	Noun	Adjective	Verb	Adverb
Simpson Desert	Yes	No	No	No
Commonwealth of Australia	Yes	No	No	No

Simpson Desert (noun)	Commonwealth of Australia (noun)
a desert region of central Australia	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