Synonyms for Commutation (same or very similar meaning)
WordNet sense 1 ((law) the reduction in severity of a punishment imposed by law):
re-sentencing
WordNet sense 2 (the travel of a commuter):
commuting
WordNet sense 3 (the act of putting one thing or person in the place of another:):
exchange, substitution
From the ODE community, based on WordNet
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