Commutation \Com`mu*ta"tion\, n. [L. commutatio: cf. F. commutation.]

1. A passing from one state to another; change; alteration; mutation. [R.]

So great is the commutation that the soul then hated only that which now only it loves. --South.

2. The act of giving one thing for another; barter; exchange. [Obs.]

The use of money is . . . that of saving the commutation of more bulky commodities. --Arbuthnot.

3. (Law) The change of a penalty or punishment by the pardoning power of the State; as, the commutation of a sentence of death to banishment or imprisonment.

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

4. A substitution, as of a less thing for a greater, esp. a substitution of one form of payment for another, or one payment for many, or a specific sum of money for conditional payments or allowances; as, commutation of tithes; commutation of fares; commutation of copyright; commutation of rations.

Angle of commutation (Astron.), the difference of the geocentric longitudes of the sun and a planet.

Commutation of tithes, the substitution of a regular payment, chargeable to the land, for the annual tithes in kind.

Commutation ticket, a ticket, as for transportation, which is the evidence of a contract for service at a reduced rate. See 2d Commute, 2.

Source: Webster's Revised Unabridged Dictionary (1913)