hebetate vs irk

hebetate

verb
  • To render obtuse; to dull; to blunt. 

adj
  • obtuse; dull 

  • Having a dull or blunt and soft point 

irk

verb
  • to irritate; annoy; bother 

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