A more thorough explanation:

Commutation means replacing one thing with another. In legal terms, it can refer to:

Commutation in criminal law means reducing or lessening a sentence or punishment given for a criminal conviction. This can be done by the governor of a state (for state convictions) or the president of the United States (for federal convictions). For example, a death sentence may be commuted to a sentence of life imprisonment. Some reasons for commutation of a sentence are good behavior, illness, old age, or when the sentence is too harsh compared to other similar cases. Commutation is different from pardon because pardon forgives the individual for the crime, while commutation only reduces the punishment.

In worker's compensation or other civil matters, commutation means replacing one form of payment with another. This can mean substituting a single payment for several periodic payments or settling on a lump sum payment.

For example, if someone is injured on the job and is entitled to receive weekly payments for their injury, they may choose to commute those payments into a lump sum payment instead. This means they will receive all the money they would have received over time in one payment.

Another example is if someone is owed money from a lawsuit settlement and they choose to commute the payments. Instead of receiving payments over time, they may choose to receive a lump sum payment instead.

These examples illustrate how commutation means replacing one thing with another, whether it be a sentence or a form of payment.