Commuted

Commuted is the past tense and past participle of the verb commute. It has several related senses.

In everyday language, to commute means to travel regularly between one’s home and a place of work or study. A person who does this is said to commute; the journey itself is called a commute. For example, “She commuted by train for ten years.”

In law, to commute a sentence means to reduce a legally imposed punishment or substitute a less severe one. A commuted sentence remains enforceable but is shorter or milder; the act is called a commutation, and it is distinct from a pardon or from parole.

In mathematics and physics, to commute means that two operations or quantities can be performed in either order without changing the result. If AB = BA, the operators A and B are said to commute. The past participle “commuted” can describe such a relationship or a transformation that yields commuting operations; in quantum mechanics, commutation relations are central to how measurements and observables relate.

Etymology: the term derives from Latin commutare, formed from com- “together” and mutare “to change.”

Usage notes: The word is ambiguous without context. In everyday speech it most often refers to travel, while in legal or scientific writing it denotes sentence reduction or a mathematical property, respectively.