\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.