Bay State vs Mass.

Bay State and Mass. both are nouns.

Word	Noun	Adjective	Verb	Adverb
Bay State	Yes	No	No	No
Mass.	Yes	No	No	No

As nouns, Bay State and Mass. are synonyms defined as:

Bay State and Mass.: a state in New England, with capital Boston; one of the original 13 colonies

Other synonyms of Bay State include MA, Massachusetts, Old Colony.

Bay State (noun)	Mass. (noun)
a state in New England, with capital Boston; one of the original 13 colonies	a state in New England, with capital Boston; one of the original 13 colonies