refusal vs waiver

refusal

noun
  • The act of refusing. 

  • Depth or point at which well or borehole drilling cannot continue. 

waiver

noun
  • The act of waiving, or not insisting on, some right, claim, or privilege. 

  • A legal document removing some requirement, such as waiving a right (giving it up) or a waiver of liability (agreeing to hold someone blameless). 

  • Something that releases a person from a requirement. 

verb
  • To waive (to relinquish, to forego). 

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