sleeping vs stertor

sleeping

noun
  • The state of being asleep, or an instance of this. 

adj
  • Asleep. 

  • Used for sleep; used to produce sleep. 

stertor

noun
  • The act of snoring, especially heavy snoring. 

  • A snoring sound, as for example even during wakefulness in infants with breathing difficulties. 

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