approbation vs say-so

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. 

say-so

noun
  • Authority, as backing some statement, injunction, or command. 

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