Massachusetts vs Mass.

Massachusetts and Mass. both are nouns.

Word	Noun	Adjective	Verb	Adverb
Massachusetts	Yes	No	No	No
Mass.	Yes	No	No	No

As nouns, Massachusetts and Mass. are synonyms defined as:

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

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

Massachusetts (noun)	Mass. (noun)
the Algonquian language of the Massachuset	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
one of the British colonies that formed the United States, with capital Salem, Charlestown or Boston
a member of the Algonquian people who formerly lived around Massachusetts Bay