island vs Hibernia

island and Hibernia both are nouns.

Word	Noun	Adjective	Verb	Adverb
island	Yes	No	No	No
Hibernia	Yes	No	No	No

island (noun)	Hibernia (noun)
a zone or area resembling an island	an island comprising the republic of Ireland and Northern Ireland
a land mass (smaller than a continent) that is surrounded by water