acerbate vs disaffect

acerbate

verb
  • To make bitter or sour. 

  • To exasperate; to irritate. 

adj
  • Embittered; having a sour disposition or nature. 

disaffect

verb
  • To cause a loss of affection, sympathy or loyalty in; to alienate or estrange. 

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