acerbate vs enrage

acerbate

verb
  • To make bitter or sour. 

  • To exasperate; to irritate. 

adj
  • Embittered; having a sour disposition or nature. 

enrage

verb
  • To fill with rage; to provoke to frenzy; to make furious. 

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