Your father's or mother's father; a grandfather, often used affectionately or in informal speech.
From 'grand' (great or large, from Old French) + 'daddy' (informal for father). Emerged in American English as a casual variant of 'grandfather' in the 19th century.
This word shows how English speakers love making up affectionate versions of family words—'grandaddy' feels cozier than the formal 'grandfather,' and different regions have their own favorites like 'grandpa,' 'papaw,' and 'granddad.'
Complete word intelligence in one call. Free tier — 50 lookups/day.