diverge vs vary

diverge

verb
  • To become different; to run apart; to separate; to tend into different directions. 

  • To separate, to tend into a different direction (from another line or path). 

  • To run apart; to separate; to tend into different directions. 

  • To become different, to separate (from another line or path). 

  • Not to converge: to have no limit, or no finite limit. 

  • Both stories start out the same way, but they diverge halfway through. 

vary

verb
  • To make of different kinds; to make different from one another; to diversity; to variegate. 

  • To embellish; to change fancifully; to present under new aspects, as of form, key, measure, etc. See variation. 

  • To be or act different from the usual. 

  • Not to remain constant: to change with time or a similar parameter. 

  • To institute a change in, from a current state; to modify. 

  • To change with time or a similar parameter. 

  • To display differences. 

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