Translation guide
How to express that something is not permitted, lacks official approval, or is done without authorization in Japanese.
Describing an action, access, or item that is not allowed or officially sanctioned.
Standard way to say 'not permitted' or 'unauthorized'. Used for actions, access, or use.
無断駐車は許可されていません。
Unauthorized parking is not permitted.
このエリアへの立ち入りは許可されていない。
Entry into this area is unauthorized.
Referring to someone who does not have the right or permission to do something.
Literally 'without authority'. Used for people lacking the proper authorization.
権限のない人はシステムにアクセスできません。
Unauthorized persons cannot access the system.
Specifically about using or copying something without permission, often in copyright contexts.
Unauthorized use. Standard term in legal/formal contexts.
画像の無断使用はご遠慮ください。
Please refrain from unauthorized use of images.
There is no single Japanese word that covers all uses of 'unauthorized'. Choose the expression based on context: permission (許可), authority (権限), or illegitimacy (不正).
無断 focuses on lack of permission, while 不正 implies illegality or wrongdoing. 不正アクセス is the standard term for hacking/unauthorized computer access, not 無断アクセス.
Prefix meaning 'without permission'. Commonly used in compounds like 無断使用 (unauthorized use), 無断転載 (unauthorized reproduction).
無断転載を禁じます。
Unauthorized reproduction is prohibited.
無断で会社のパソコンを使った。
I used the company computer without authorization.
Means 'illegitimate' or 'unauthorized', often implying wrongdoing. Used in terms like 不正アクセス (unauthorized access).
不正アクセスが発覚した。
Unauthorized access was detected.
Specifically means 'not officially authorized/licensed', used for regulated activities or products.
この薬はまだ認可されていない。
This drug is still unauthorized.
Means 'without permission'. Can modify a person or action.
許可のない者は立ち入り禁止です。
Unauthorized persons are prohibited from entering.
Outsider; person not belonging to the group/organization. Often used in signs.
部外者立ち入り禁止。
No unauthorized entry. (Outsiders prohibited.)
Unauthorized reproduction/reprinting. Very common on websites.
当サイトの文章の無断転載を禁止します。
Unauthorized reproduction of text from this site is prohibited.
Unauthorized duplication/copying. Often used for physical media or documents.
このCDの無断複製は法律で禁じられています。
Unauthorized duplication of this CD is prohibited by law.