acerbate vs flip out

acerbate

verb
  • To make bitter or sour. 

  • To exasperate; to irritate. 

adj
  • Embittered; having a sour disposition or nature. 

flip out

verb
  • To become very angry or upset. 

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