beat off vs rebut

beat off

verb
  • To drive something away with blows or military force. 

  • To waste time. 

  • To masturbate, usually a man of himself. 

rebut

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

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

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