Old North State vs N.C.

Old North State and N.C. both are nouns.

Word	Noun	Adjective	Verb	Adverb
Old North State	Yes	No	No	No
N.C.	Yes	No	No	No

As nouns, Old North State and N.C. are synonyms defined as:

Old North State and N.C.: a state in southeastern United States; one of the original 13 colonies

Other synonyms of Old North State include NC, North Carolina, Tar Heel State.

Old North State (noun)	N.C. (noun)
a state in southeastern United States; one of the original 13 colonies	a state in southeastern United States; one of the original 13 colonies