approbation vs assent

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. 

assent

noun
  • agreement; act of agreeing 

verb
  • To agree to a proposal. 

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