Mona vs island

Mona and island both are nouns.

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

Mona (noun)	island (noun)
an island to the northwest of Wales	a zone or area resembling an island
	a land mass (smaller than a continent) that is surrounded by water