approval vs rebuttal

approval

noun
  • An expression granting permission; an indication of agreement with a proposal; an acknowledgement that a person, thing, or event meets requirements. 

  • Something mailed by a seller to a collector to match their stated interests; the collector can approve of or return the item. 

  • An expression of favorable acceptance and encouragement; a compliment that also condones. 

rebuttal

noun
  • The act of contradicting something by making a contrary argument, or presenting contrary evidence. 

  • A statement, designed to refute or negate specific arguments put forward by opponents. 

  • A pleading by a defendant in reply to the evidence put forward by a plaintiff or the prosecution. 

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