approval vs disbelief

approval

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

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

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

disbelief

noun
  • Astonishment. 

  • Unpreparedness, unwillingness, or inability to believe that something is the case. 

  • The loss or abandonment of a belief; cessation of belief. 

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