rebut vs ward off

rebut

verb
  • To drive back or beat back; to repulse. 

  • To deny the truth of something, especially by presenting arguments that disprove it. 

ward off

verb
  • To parry, or turn aside. 

  • To avert or prevent. 

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