Mala fides

Bad faith (Latin: mala fides) is a legal concept in which a malicious motive on the part of a party in a lawsuit undermines their case. It has an effect on the ability to maintain causes of action and obtain legal remedies. Generally speaking, courts will not just look at the legal rights of parties in pursuing a transaction or a lawsuit, but will look behind the activity at the motives of the persons attempting to obtain the assistance of the court. If a court feels that the reasons behind the transaction or lawsuit have the effect of abusing the power of the law, or the court, it will generally deny a party the ability to rely on a legal remedy that they will otherwise be entitled to.
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Bad faith (from French, mauvaise foi) is a philosophical concept first coined by existentialist philosopher Jean-Paul Sartre to describe the phenomenon wherein one denies one's total freedom, instead choosing to behave as an inert object. It is closely related to the concept of self-deception and Friedrich Nietzsche's concept of ressentiment.
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La malafede (dal latino mala fides) è una motivazione comportamentale per la quale un individuo agisce in modo formalmente corretto, sebbene mascherando le proprie intenzioni in modo da non far trapelare gli obiettivi che realmente persegue. Il termine è più propriamente usato con riferimento alla condotta di colui che sia in relazione falsamente franca con taluno, qualora stia cercando di procurarsi un vantaggio a scapito del suo interlocutore.
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bad faith, evil intent, intent to cheat

不誠実

sans générosité, qui n'est pas généreux