Accord and Satisfaction

agreement whereby both sides waive part of their claims (Law)

In contract law, accord and satisfaction is the purchase of the release from a debt obligation. The payment is typically less than what is owed and is not paid by the actual performance of the original obligation. The accord is the agreement to discharge the obligation and the satisfaction is the legal "consideration" which binds the parties to the agreement.
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Noun
1. the settlement of a debt by paying less than the amount demanded in exchange for extinguishing the debt
(hypernym) settlement

A term of contract law by which one party, having complied with its obligation under a contract, accepts some type of compensation from the other party (usually money and of a lesser value) in lieu of enforcing the contract and holding the other party to their obligation. - (read more on Accord and Satisfaction)