indirect vs substitutional

indirect

adj
  • Not focused straight at the target or subject, but by more subtle means 

  • Not of obvious or immediate cause, but as a secondary result 

  • Not involving the quickest, shortest, or most convenient path 

noun
  • An indirect cost. 

  • An indirect radiator 

verb
  • To access by means of indirection; to dereference. 

substitutional

adj
  • Of or pertaining to substitution or to a substitute 

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