Anglesey vs Mona

Anglesey and Mona both are nouns.

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

As nouns, Anglesey and Mona are synonyms defined as:

Other synonyms of Anglesey include Anglesea, Anglesea Island, Anglesey Island.

Anglesey (noun)	Mona (noun)
an island to the northwest of Wales	an island to the northwest of Wales