Translation guide
The quality of being not guided by or based on good sense; the state of being excessive, unfair, or irrational. This concept is expressed in Japanese through various nouns, adjectives, and set phrases depending on the nuance.
Describing something that is irrational, illogical, or not based on sound reasoning.
A formal noun/adjective meaning 'irrationality' or 'unreasonableness'. Often used in logical, academic, or business contexts.
その提案は不合理だ。
That proposal is unreasonable.
Emphasizes unfairness and lack of reason, often with emotional weight. Commonly used for situations that feel unjust or absurd.
理不尽な要求には応じられない。
I can't comply with unreasonable demands.
A phrase meaning 'it doesn't make sense' or 'it's illogical'. Used when an argument or action lacks coherence.
彼の説明は筋が通らない。
His explanation is unreasonable.
Describing something that goes beyond acceptable limits, often in demands, prices, or behavior.
A very common word meaning 'impossible', 'unreasonable', or 'excessive'. Used for requests, expectations, or situations that are too much to handle.
それは無理な注文だ。
That's an unreasonable order.
Means 'exorbitant' or 'outrageous', especially for prices or demands. Stronger than 無理 in terms of excess.
A formal term for 'excessive' or 'undue'. Often used in written or technical contexts.
過度な要求は控えてください。
Please refrain from unreasonable demands.
Describing a situation or treatment that is not fair or equitable.
Means 'unjust' or 'unfair'. Often used in legal, social, or workplace contexts to describe treatment or decisions.
不当な扱いを受けた。
I received unreasonable treatment.
Directly means 'unfair' or 'inequitable'. Common in everyday speech.
Describing a person who refuses to listen to reason or is willfully irrational.
Means 'tyrannical' or 'high-handed'. Used for someone who acts unreasonably and oppressively, often in a position of power.
上司の横暴な態度に耐えられない。
I can't stand my boss's unreasonable attitude.
Literally 'can't get through to them'. Describes someone who won't listen to reason.
彼は話が通じない。
He is unreasonable.
不合理 is more objective and logical, while 理不尽 carries a stronger emotional charge of unfairness and absurdity. Use 不合理 for factual unreasonableness and 理不尽 when expressing frustration.
The English word 'unreasonable' covers many nuances. Direct translation as '非合理的' is rarely used. Choose the Japanese term that matches the specific context: logic, excess, unfairness, or stubbornness.
法外な値段を請求された。
I was charged an unreasonable price.
そのルールは不公平だ。
That rule is unreasonable.