1An adult; a grown-up — a person who has physically and socially matured, as opposed to a child. The everyday word for an adult in modern Japanese. Also used adjectivally (大人な, 大人の) to describe calm, mature behavior, as in 大人な対応 (a grown-up response). Read as おとな (jukujikun).
もう大人なんだから、自分のことは自分で決めなさい。
You're an adult now, so make your own decisions.
子どもの頃は早く大人になりたかったが、いざなってみると大変なことばかりだ。
When I was a kid I wanted to grow up fast, but now that I have, it's nothing but hard work.
彼女はあの場面で感情的にならず、大人な対応をした。
Rather than getting emotional in that situation, she handled it in a mature way.
この映画は大人向けで、子どもには少し難しいかもしれない。
This movie is aimed at adults — it might be a bit hard for kids to follow.
ここは大人になっても帰ってきたくなる町だ。
This is a town you'll want to come back to even after you grow up.