catnap vs turn in

catnap

verb
  • To take a catnap (short sleep or nap). 

  • To kidnap a cat. 

noun
  • A brief, light sleep, usually during the daytime. 

turn in

verb
  • To go to bed; to retire to bed. 

  • To convert a goal using a turning motion of the body. 

  • To relinquish; give up; to tell on someone to the authorities (especially to turn someone in). 

  • To submit something; to give. 

  • To reverse the ends of threads and insert them back into the piece being woven so they do not protrude and eventually unravel. 

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