Channel Island vs island

Channel Island and island both are nouns.

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

Channel Island (noun)	island (noun)
any of a group of British islands in the English Channel off the northern coast of France	a zone or area resembling an island
	a land mass (smaller than a continent) that is surrounded by water