descending vs turndown

descending

noun
  • A descent. 

adj
  • Ordered such that each element is less than or equal to the previous element. 

  • Moving or sloping downwards. 

  • Becoming lower in pitch. 

  • Causing a sequence to follow a descending order. 

turndown

noun
  • A downturn. 

  • The operational range of a device 

  • A rejection. 

  • A downward pointing extension to a vehicle muffler. 

  • The service of turning down the bedcovers and often leaving chocolates, etc., on the pillow. 

adj
  • Made to wear with the upper part turned down. 

  • Capable of being turned down, or decreased in intensity. 

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