napping vs sleeping

napping

noun
  • The act of taking a nap or short sleep. 

  • The act or process of raising a nap, as on cloth. 

sleeping

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

adj
  • Asleep. 

  • Used for sleep; used to produce sleep. 

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