consent vs imprimatur

consent

noun
  • Voluntary agreement or permission. 

verb
  • To express willingness, to give permission. 

  • To cause to sign a consent form. 

  • To agree in opinion or sentiment; to be of the same mind; to accord; to concur. 

imprimatur

noun
  • Any mark of official approval. 

  • An official license to publish or print something, especially when censorship applies. 

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