keen vs shallow

keen

verb
  • To make cold, to sharpen. 

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

  • To mourn. 

  • To utter a keen. 

adj
  • 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. 

  • Fierce, intense, vehement. 

noun
  • A prolonged wail for a deceased person. 

shallow

verb
  • To make or become less deep. 

noun
  • A costermonger's barrow. 

  • A shallow portion of an otherwise deep body of water. 

  • A fish, the rudd. 

adj
  • Not steep; close to horizontal. 

  • Not far forward, close to the net. 

  • Having little depth; significantly less deep than wide. 

  • Not intellectually deep; not penetrating deeply; simple; not wise or knowing. 

  • Concerned mainly with superficial matters. 

  • Extending not far downward. 

  • Lacking interest or substance. 

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