approbation vs refusal

approbation

noun
  • The act of approving; an assenting to the propriety of a thing with some degree of pleasure or satisfaction; approval, sanction, commendation or official recognition. 

refusal

noun
  • The act of refusing. 

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

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