acerbate vs discountenance

acerbate

verb
  • To exasperate; to irritate. 

  • To make bitter or sour. 

adj
  • Embittered; having a sour disposition or nature. 

discountenance

verb
  • To abash, embarrass or disconcert. 

  • To refuse countenance or support to; to discourage. 

  • To have an unfavorable opinion of; to deprecate or disapprove of. 

noun
  • Cold treatment; disapprobation. 

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