septuagenarian
🇺🇸
/ˌseptʃuədʒəˈneriən/
🇬🇧
/ˌseptjuədʒəˈneəriən/
A person who is between 70 and 79 years old.
My grandfather is a healthy septuagenarian who still enjoys hiking.
내 할아버지는 여전히 하이킹을 즐기는 건강한 70대입니다.