nanna vs gran

nanna and gran both are nouns.

Word	Noun	Adjective	Verb	Adverb
nanna	Yes	No	No	No
gran	Yes	No	No	No

As nouns, nanna and gran are synonyms defined as:

Other synonyms of nanna include grandma, grandmother, grannie, granny, nan.

nanna (noun)	gran (noun)
the mother of your father or mother	the mother of your father or mother