Lanai Island vs island

Lanai Island and island both are nouns.

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

Lanai Island (noun)	island (noun)
an island of central Hawaii; a pineapple-growing area	a zone or area resembling an island
	a land mass (smaller than a continent) that is surrounded by water