Fetching details from the dictionary...

adult; grown-up
「大人」 has other readings with different meanings.
大人になったら何になりたい。
What do you want to be when you grow up?
大人でも泣きたい時はあるよ。
Even adults have times when they want to cry.
大人になってから子供の頃の思い出がますます大切に感じる。
After becoming an adult, childhood memories feel increasingly precious.