declass vs rebut

declass

verb
  • To remove from a class. 

  • To lower the class or social standing of. 

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 declass and rebut occurred in a corpus of books? (source: Google Ngram Viewer )