Norman-French vs Old North French

Norman-French and Old North French both are nouns.

Word	Noun	Adjective	Verb	Adverb
Norman-French	Yes	No	No	No
Old North French	Yes	No	No	No

As nouns, Norman-French and Old North French are synonyms defined as:

Norman-French and Old North French: the medieval Norman dialect of Old French

Other synonyms of Norman-French include Norman French.

Norman-French (noun)	Old North French (noun)
the medieval Norman dialect of Old French	the medieval Norman dialect of Old French