四よん十じゅう代だい

noun

one's 40s; forties

Refers to the age decade from 40 to 49 years old. Used for people, and sometimes for eras or periods.

• 彼かれは四よん十じゅう代だいで会かい社しゃを辞やめた。

  He quit his company in his forties.

• ４０代だいの女じょ性せいに人にん気きの趣しゅ味みは何なんですか。

  What hobbies are popular among women in their 40s?