incessive vs keen

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. 

keen

adj
  • Fierce, intense, vehement. 

  • Often with a prepositional phrase, or with to and an infinitive: showing a quick and ardent responsiveness or willingness; eager, enthusiastic, interested. 

  • Acute of mind, having or expressing mental acuteness; penetrating, sharp. 

  • Having a fine edge or point; sharp. 

  • Of cold, wind, etc.: cutting, penetrating, piercing, sharp. 

  • Of prices, extremely low as to be competitive. 

  • Acrimonious, bitter, piercing. 

noun
  • A prolonged wail for a deceased person. 

verb
  • To utter with a loud wailing voice or wordless cry. 

  • To mourn. 

  • To make cold, to sharpen. 

  • To utter a keen. 

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