diabolical vs incessive

diabolical

adj
  • Extremely wicked or cruel. 

  • Of or concerning the devil; satanic. 

incessive

adj
  • Fierce; cruel and aggressive. 

  • Insightful; deep and succinct; incisive. 

  • Intruding inward. 

  • Tending to incite or inflame; incensive. 

  • Intense and active. 

  • Synonym of inessive 

  • Continual or successive; unceasing. 

  • Critical and accurate; incisive. 

  • Included. 

  • Durative. 

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