substitution vs commutation

substitution and commutation both are nouns.

Word	Noun	Adjective	Verb	Adverb
substitution	Yes	No	No	No
commutation	Yes	No	No	No

As nouns, substitution and commutation are synonyms defined as:

substitution and commutation: the act of putting one thing or person in the place of another:

Other synonyms of substitution include exchange.

substitution (noun)	commutation (noun)
the act of putting one thing or person in the place of another:	the travel of a commuter
an event in which one thing is substituted for another	(law) the reduction in severity of a punishment imposed by law
	the act of putting one thing or person in the place of another:
	a warrant substituting a lesser punishment for a greater one