Added 8 October 2026 grandad noun Categories: PeopleRare Words noun ! Definition from WordNet 3.1, Princeton University. More about grandad at Wordnik → Where our words come from → The father of your father or mother. Related Words: granddadgranddaddygrandfathergrandpagrampsgrandpapagreat-grandfathergrampapopsgrandparentgrandmaold Back to today's word