unconscionable

Definition from Nolo’s Plain-English Law Dictionary

When one party to a contract takes advantage of the other due to unequal bargaining positions, perhaps because of the disadvantaged party's recent trauma, physical infirmity, ignorance, inability to read, or inability to understand the language. A contract will be terminated as unconscionable if the unfairness is so severe that it is shocking to the average person.

Definition provided by Nolo’s Plain-English Law Dictionary.