commute

v. (-ting) 1 travel some distance to and from work. 2 (usu. Foll. By to) change (a punishment) to one less severe. 3 (often foll. By into, for) change (one kind of payment or obligation) for another. 4 exchange.  commutable adj. Commutation n. [latin muto change]

v. t. To exchange; to put or substitute something else in place of, as a smaller penalty, obligation, or payment, for a greater, or a single thing for an aggregate; hence, to lessen; to diminish; as, to commute a sentence of death to one of imprisonment for life; to commute tithes; to commute charges for fares.