crowning vs imperatorial

crowning

adj
  • Supreme; of a surpassing quality or quantity. 

noun
  • The stage of vaginal childbirth when the infant's head remains consistently visible at the vulva. 

  • A coronation. 

  • The act of one who crowns (in various senses). 

imperatorial

adj
  • Commanding; authoritative. 

  • Relating to the title or office of imperator. 

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