acerbate vs get at

acerbate

verb
  • To exasperate; to irritate. 

  • To make bitter or sour. 

adj
  • Embittered; having a sour disposition or nature. 

get at

verb
  • To attack verbally or physically; to annoy, bother. 

  • To manage to gain access to. 

  • To understand or ascertain by investigation. 

  • To persuade by intimidation, to tamper with. 

  • To begin working on or dealing with. 

  • To contact someone. 

  • To mean, signify. 

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