island vs Porto Rico

island and Porto Rico both are nouns.

Word	Noun	Adjective	Verb	Adverb
island	Yes	No	No	No
Porto Rico	Yes	No	No	No

island (noun)	Porto Rico (noun)
a zone or area resembling an island	a self-governing commonwealth associated with the United States occupying the island of Puerto Rico
a land mass (smaller than a continent) that is surrounded by water	the smallest and easternmost of the Greater Antilles in the Caribbean