regrade vs repulse

regrade

verb
  • To regroup or reassign. 

  • To change the classification of (potentially secret documentation). 

  • To grade again, give a new grade or grading to. 

noun
  • The act or process of grading again. 

repulse

verb
  • To repel or drive back. 

  • To reject or rebuff. 

  • To cause revulsion in. 

noun
  • the act of repulsing or the state of being repulsed 

  • refusal, rejection or repulsion 

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