How to say "great-grandfather" in Japanese

• 曽祖父そうそふ
  nounThe kanji term for a grandparent's father, read そうそふ. It names the relationship precisely, which suits family trees, genealogies and other writing about ancestors.
  曾祖父そうそふの代だいから東京とうきょうに住すんでいます。↗

  My family came to live in Tokyo in my great-grandfather's time.
• 大祖父おおおおじ
  nounAn uncommon kanji compound for great-grandfather, read おおおおじ. It is seldom the word you actually want; for this relationship, 曽祖父 or ひいおじいさん is the safer choice.
• ひいおじいさん
  nounThe word you normally hear for a grandparent's father in conversation, usually written in kana alone. It feels familiar and affectionate, fitting everyday family talk.
• 大じじおおじじ
  nounA very casual, jokey variant built on じじ, an informal word for a grandfatherly old man. It is seldom the word you want for great-grandfather; ひいおじいさん is the everyday choice.

All four mean a grandparent's father, so choose by tone: 曽祖父 for writing and precise statements of the relationship, 「ひいおじいさん」 for everyday conversation, while 大祖父 is rare and 「大じじ」 is casual slang.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 曽祖父そうそふgreat-grandfather
• 大祖父おおおおじgreat-grandfather
• ひいおじいさんgreat-grandfather
• 大じじおおじじgreat-grandfather