Translation guide
Describes a person, action, or attitude that lacks a sense of responsibility, fails to consider consequences, or is careless and unreliable. Japanese expressions vary by nuance: moral blame, thoughtlessness, lack of planning, or untrustworthiness.
To describe a person or behavior that is morally or socially irresponsible, often implying negligence or disregard for duty.
The most direct and common translation. Used for people, remarks, or actions that are irresponsible and show a lack of accountability.
彼の無責任な発言に驚いた。
I was surprised by his irresponsible remark.
そんな無責任な態度は許せない。
I can't forgive such an irresponsible attitude.
Predicate form used to say someone or something is irresponsible.
彼は本当に無責任だ。
He is really irresponsible.
Literally 'has no sense of responsibility.' Describes a person's character rather than a single action.
あの人は責任感がないから、大事な仕事は任せられない。
That person has no sense of responsibility, so I can't entrust important work to them.
To describe actions or decisions made without thinking about the negative outcomes, often impulsive or reckless.
Means rash, thoughtless, or imprudent. Often used for hasty actions or remarks that lead to trouble.
軽率な行動で会社に損害を与えた。
His rash actions caused damage to the company.
軽率な発言をしてしまい、後悔している。
I made a thoughtless remark and regret it.
Indiscreet, imprudent, lacking good judgment. Slightly formal and often used in written contexts.
Literally 'without thinking.' Casual and direct, often used in spoken criticism.
考えなしにそんなことを言うなんて、ひどいよ。
Saying something like that without thinking is terrible.
To describe a person who cannot be depended on to do what they should, often letting others down.
Means irresponsible, half-hearted, or sloppy. Commonly used for people who don't take things seriously.
彼は仕事がいい加減で、よくミスをする。
He is irresponsible in his work and often makes mistakes.
いい加減な約束はしないでほしい。
I wish you wouldn't make half-hearted promises.
Also covers unreliability when someone shirks duties.
Not serious, lacking diligence. Often used in school or work contexts for someone who doesn't try hard.
To describe someone who avoids accountability, makes excuses, or blames others.
Literally 'does not take responsibility.' Directly describes failure to accept consequences.
彼はいつも責任を取らない。
He never takes responsibility.
Means 'blame others.' Implies irresponsibility through shifting fault.
失敗を人のせいにするのは無責任だ。
Blaming others for your mistakes is irresponsible.
無責任 (むせきにん) focuses on lack of accountability and moral responsibility. いい加減 (いいかげん) emphasizes sloppiness, half-heartedness, and unreliability. A person can be いい加減 without being morally blameworthy, but 無責任 usually carries a stronger negative judgment.
Avoid directly translating 'irresponsible' as 無責任 in all cases. For example, 'irresponsible spending' is better translated as 計画性のない支出 (spending without planning) or 無駄遣い (wasteful spending), not 無責任な支出.
無分別な投資で財産を失った。
He lost his fortune through imprudent investments.
無責任な人に頼むと、後で困ることになる。
If you ask an irresponsible person, you'll regret it later.
Irresponsible students tend to fail their courses.