A more thorough explanation:

Definition: Rachat (rah-shah), n. [French] 1. The act of buying back something that was previously sold or lost. 2. Payment made to release someone from captivity or punishment.

• After losing his car to the bank, John was able to get it back through a rachat agreement.
• The kidnappers demanded a large sum of money as rachat for the safe return of the businessman.

The first example illustrates the first definition of rachat, where something that was previously sold or lost is bought back. In this case, John's car was bought back through a rachat agreement with the bank.

The second example illustrates the second definition of rachat, where payment is made to release someone from captivity or punishment. In this case, the kidnappers demanded a ransom (or rachat) for the safe return of the businessman.