commutation vs peregrination

commutation

noun
  • The process or habit of journeying to and from work on a regular basis; commuting. 

  • The reversal of an electric current. 

  • The change to a lesser penalty or punishment by the State 

  • Substitution, as a means of discriminating between phonemes. 

  • Substitution of one thing for another; interchange. 

  • Specifically, the substitution of one kind of payment for another, especially a switch to monetary payment from obligations of labour. 

peregrination

noun
  • A journey or trip, especially by foot; also (uncountable) journeying, travelling. 

  • Straying from the main subject in speech or writing; digression; (countable) an instance of this. 

  • Broad or systematic discussion of a subject; (countable) an instance of this; a discourse. 

How often have the words commutation and peregrination occurred in a corpus of books? (source: Google Ngram Viewer )