Answer:
Accord and satisfaction
Explanation:
Accord and satisfaction is the legal term that we use when two people a creditor and a debtor dispute an amount of money that the creditor lended to the debtor.
The debtor has the opportunity to come to terms with the creditor by reaching and accord and satisfaction the debtor can send a paid in full check which basically means that if the debtor cashes in that check he agrees to lower or settle for the amount the debtor has send in the check for the full amount of the debt.
So in this case the creditor will be accepting a $500 agreement with the debtor for the full $1000 debt.