island vs Martha's Vineyard

island and Martha's Vineyard both are nouns.

Word	Noun	Adjective	Verb	Adverb
island	Yes	No	No	No
Martha's Vineyard	Yes	No	No	No

island (noun)	Martha's Vineyard (noun)
a zone or area resembling an island	an island summer resort off of Cape Cod
a land mass (smaller than a continent) that is surrounded by water