approval vs rebuff

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. 

rebuff

noun
  • Repercussion, or beating back. 

  • He was surprised by her quick rebuff to his proposal. 

  • A sudden resistance or refusal. 

verb
  • To refuse; to offer sudden or harsh resistance; to turn down or shut out. 

  • To buff again. 

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