granddaddy vs grandfather

granddaddy and grandfather both are nouns.

Word	Noun	Adjective	Verb	Adverb
granddaddy	Yes	No	No	No
grandfather	Yes	No	No	No

As nouns, granddaddy and grandfather are synonyms defined as:

Other synonyms of granddaddy include gramps, grandad, granddad, grandpa.

granddaddy (noun)	grandfather (noun)
the father of your father or mother	the father of your father or mother