island vs Guadalupe Island

island and Guadalupe Island both are nouns.

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

island (noun)	Guadalupe Island (noun)
a zone or area resembling an island	a Mexican island in the Pacific to the west of Baja California
a land mass (smaller than a continent) that is surrounded by water