Norfolk Island vs island

Norfolk Island and island both are nouns.

Word	Noun	Adjective	Verb	Adverb
Norfolk Island	Yes	No	No	No
island	Yes	No	No	No

Norfolk Island (noun)	island (noun)
an island territory of Australia in the Pacific Ocean off the eastern coast of Australia; formerly a British penal colony	a zone or area resembling an island
	a land mass (smaller than a continent) that is surrounded by water