Translation guide
The English word "grown-up" can refer to an adult person or to mature, responsible behavior. In Japanese, the most common equivalent is 大人 (otona), but depending on context, other expressions like 成人 (seijin) or phrases describing maturity are used. This guide covers how to express these meanings naturally.
Referring to someone who is no longer a child, an adult.
The standard word for 'adult' or 'grown-up'. Used in everyday conversation.
彼はもう大人だ。
He is already a grown-up.
大人になったら何になりたい？
What do you want to be when you grow up?
Refers to a legal adult, someone who has reached the age of majority (20 in Japan). More formal than 大人.
日本では20歳で成人とみなされる。
In Japan, you are considered an adult at age 20.
Literally 'adult person'. Used when you need to specify 'person', e.g., when contrasting with children.
大人の人は子供より高い料金です。
Adults are charged more than children.
Hiragana spelling of 大人, often used in children's contexts or to soften the tone.
おとなはコーヒーが好きだよね。
Grown-ups like coffee, right?
Describing behavior, attitude, or appearance that is mature, responsible, or characteristic of an adult.
An i-adjective meaning 'adult-like', 'mature', or 'grown-up'. Used for people or things that seem mature.
彼女はとても大人っぽいね。
She seems very grown-up, doesn't she?
その服、大人っぽく見えるよ。
That outfit makes you look grown-up.
Means 'adult-like' in the sense of behaving in a way befitting an adult, often with a nuance of responsibility or propriety.
大人らしい態度を取りなさい。
Behave like a grown-up.
Describes someone who is reliable, steady, and mature. Often used for children who act grown-up.
あの子はまだ10歳なのに、とてもしっかりしている。
That child is only 10, but very grown-up.
Means 'mature' or 'ripened'. More formal and often used for abstract qualities or in written language.
彼は成熟した考え方を持っている。
He has a mature way of thinking.
Referring to things, activities, or content intended for adults, not children.
Means 'for adults' or 'aimed at adults'. Used for products, events, etc.
これは大人向けの映画です。
This is a grown-up movie.
Simply 'adult's' or 'for adults'. Can imply sophistication or maturity.
大人の時間を楽しみましょう。
Let's enjoy some grown-up time.
In English, 'grown-up' can be an adjective (e.g., 'a grown-up attitude'). In Japanese, you cannot simply use 大人 as an adjective. Use 大人っぽい or 大人らしい instead.
大人っぽい態度
a grown-up attitude
大人 is the general word for adult, while 成人 specifically refers to legal adulthood. Use 成人 when discussing age of majority, coming-of-age ceremonies, or legal rights.
成人式
Coming-of-Age Day ceremony