American Dictionary of the English Language

COMMUTATION, noun

1. Change; alteration; a passing from one state to another.

2. Exchange; the act of giving one thing for another; barter.

The use of money is to save the commutation of more bulky commodities.

3. In law, the change of a penalty or punishment from a greater to a less; as banishment instead of death.

Suits are allowable in the spiritual courts for money agreed to be given as a commutation for penance.