[kom-yuh-tey-shuh
n] 
| 1. | the act of substituting one thing for another; substitution; exchange. |
| 2. | the changing of a prison sentence or other penalty to another less severe. |
| 3. | the act of commuting, as to and from a place of work. |
| 4. | the substitution of one kind of payment for another. |
| 5. | Electricity. the act or process of commutating. |
| 6. | Also called commutation test. Linguistics. the technique, esp. in phonological analysis, of substituting one linguistic item for another while keeping the surrounding elements constant, used as a means of determining the constituent units in a sequence and their contrasts with other units. |