'granddad' originates from the English word 'grandfather,' where 'grand' meant 'large' or 'important' and 'father' referred to a male parent.

'grandfather' transformed into the colloquial term 'granddad' in the 19th century, reflecting a more affectionate and familiar form of address.

Initially, it meant 'a male ancestor,' but over time it evolved into a more affectionate term for one's grandfather.