ひいおじいさんMeaningsNoun1. great-grandfather (Usually kana)Other spellings曾ひいおじいさん曾ひいお祖父じいさん曽ひいお祖父じいさんUsually written in kanaKanji in other spellings曾formerly [old]祖grandparent父father曽great (grandparent or grandchild)