嫡ちゃく孫そん

noun

eldest son's descendants; lineal descendants through the eldest son

Formal term used in legal, historical, or family-register contexts referring to the direct line of descent from the eldest son. Not an everyday word.

• 旧きゅう民みん法ぽうでは、嫡ちゃく孫そんが家か督とくを継つぐことが定さだめられていた。

  Under the old Civil Code, it was stipulated that the lineal descendants of the eldest son would succeed to the family headship.