cocoon vs cut off

cocoon

verb
  • To envelop in a protective case. 

  • To withdraw into such a case. 

noun
  • The silky protective case spun by the larvae of some insects in which they metamorphose, the pupa. 

  • Any similar protective case, whether real or metaphorical. 

cut off

verb
  • To isolate or remove from contact. 

  • To remove via cutting. 

  • To turn off or switch off (an electrical device). 

  • (North American) swerve in front of (another car) while driving; cut [someone] up 

  • To interrupt (someone speaking). 

  • To end abruptly. 

  • To stop providing funds to (someone). 

  • To stop the provision or supply of something, e.g. power, water. 

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