gran vs granny

gran and granny both are nouns.

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

As nouns, gran and granny are synonyms defined as:

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

gran (noun)	granny (noun)
the mother of your father or mother	a reef knot crossed the wrong way and therefore insecure
	the mother of your father or mother
	an old woman