cinch vs peg down

cinch

verb
  • To bring to certain conclusion. 

  • To tighten down. 

  • In the game of cinch, to protect (a trick) by playing a higher trump than the five. 

noun
  • Something that is very easy to do. 

  • A firm hold. 

  • A variety of auction pitch in which a draw to improve the hand is added, and the five of trumps (called "right Pedro") and the five of the same colour (called "left Pedro", and ranking between the five and the four of trumps) are each worth five. Fifty-one points make a game. 

  • A simple saddle girth used in Mexico. 

  • Something that is obvious or certain to occur; a sure thing. 

peg down

verb
  • To identify clearly. 

  • To fasten something to the ground using pegs. 

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