na-adjective, noun
Describes something that is not reasonable, not feasible, or cannot be done. Covers both logical impossibility and practical infeasibility.
この計画は無理だと思う。
I think this plan is impossible.
そんな無理な要求には応じられない。
I can't comply with such an unreasonable demand.
na-adjective, noun
Often used adverbially as 無理に to mean doing something forcibly or against someone's will.
無理に食べさせるのはよくない。
It's not good to force someone to eat.
彼は無理に笑った。
He forced a smile.
na-adjective
excessive; overdoing
Refers to pushing oneself too hard, overworking, or doing something beyond one's limits. The verb form 無理する is common.
無理なダイエットは体に悪い。
Excessive dieting is bad for your health.
あまり無理しないでください。
Please don't overdo it.
interjection
no way!; impossible!
Colloquial interjection expressing strong disbelief or refusal.
「明日までに終わる？」「無理！」
"Can you finish by tomorrow?" "No way!"
noun which may take the genitive case particle 'no'
Mathematical term for irrational numbers.
√2は無理数である。
√2 is an irrational number.
Compound of 無 (mu, 'without') and 理 (ri, 'reason, principle'). The literal meaning is 'without reason', which developed into 'unreasonable' and related senses.