じいじMeanings1noungrandpa; grampschildren's languageChildish or affectionate term for one's own grandfather, similar to 'grandpa' or 'gramps' in English. Used by young children or within the family.See also: おじいさんじいじ、遊あそぼう!Grandpa, let's play!今日きょうはじいじの家いえに行いくんだ。