defence vs refutation

defence

noun
  • An argument in support or justification of something. 

  • A strategy and tactics employed to prevent the other team from scoring; contrasted with offence. 

  • The portion of a team dedicated to preventing the other team from scoring; contrasted with offence. 

  • Government policy or (infra)structure related to the military. 

  • Something used to oppose attacks. 

  • The action of defending, of protecting from attack, danger or injury. 

refutation

noun
  • A vocal answer to an attack on one's assertions. 

  • An act of refuting or disproving; the disproving of an argument, opinion, testimony, doctrine or theory by argument or countervailing proof; evidence of falseness. 

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