cot vs penthouse

cot

noun
  • A bed for infants or small children, with high, often slatted, often moveable sides. 

  • A cover or sheath; a fingerstall. 

  • A simple bed, especially one for portable or temporary purposes. 

  • A wooden bed frame, slung by its corners from a beam, in which officers slept before the introduction of bunks. 

  • A pen, coop, or similar shelter for small domestic animals, such as sheep or pigeons. 

  • A small, crudely-formed boat. 

penthouse

noun
  • An apartment or suite found on an upper floor, or floors, of a tall building, especially one that is expensive or luxurious with panoramic views. Sometimes these are located just under "penthouse mechanical" floors. 

  • Any of the sloping roofs at the side of a real tennis court. 

  • An outhouse or other structure (especially one with a sloping roof) attached to the outside wall of a building, sometimes as protection from the weather. 

verb
  • To provide with a penthouse, shelter by means of a shed sloping from a wall, or anything similar. 

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