beat off vs repel

beat off

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

  • To waste time. 

  • To masturbate, usually a man of himself. 

repel

verb
  • To force away by means of a repulsive force. 

  • To ward off (a malignant influence, attack etc.). 

  • To drive back (an assailant, advancing force etc.). 

  • To cause repulsion or dislike in; to disgust. 

  • To reject, put off (a request, demand etc.). 

  • To save (a shot). 

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