languish vs zonk out

languish

verb
  • To pine away in longing for something; to have low spirits, especially from lovesickness. 

  • To be neglected; to make little progress, be unsuccessful. 

  • To live in miserable or disheartening conditions. 

  • To lose strength and become weak; to be in a state of weakness or sickness. 

zonk out

verb
  • To fall suddenly into a very deep sleep. 

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