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unfair; unjust; wrongful; improper; unreasonable; unwarranted; unjustified; undeserved; undue
その扱いは明らかに不当だと思う。
I think that treatment is clearly unjust.
不当な要求には絶対に応じられません。
I absolutely cannot comply with unjust demands.
不当解雇で会社を訴えることにした。
I decided to sue the company for wrongful termination.