commutable

from WordNet (r) 3.0 (2006)

commutable
    adj 1: subject to alteration or change; "the death sentence was
           commutable to life imprisonment" [ant: {incommutable}]
    2: capable of being exchanged for another or for something else
       that is equivalent [syn: {commutable}, {substitutable}]

from The Collaborative International Dictionary of English v.0.48

Commutable \Com*mut"a*ble\, a. [L. commutabilis.]
   Capable of being commuted or interchanged.
   [1913 Webster]

         The predicate and subject are not commutable.
                                                  --Whately.
   [1913 Webster]

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