cinch vs untie

cinch

verb
  • To tighten down. 

  • To bring to certain conclusion. 

  • 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. 

untie

verb
  • To loosen, as something interlaced or knotted; to disengage the parts of. 

  • In the Perl programming language, to undo the process of tying, so that a variable uses default instead of custom functionality. 

  • To resolve; to unfold; to clear. 

  • To become untied or loosed. 

  • To free from fastening or from restraint; to let loose; to unbind. 

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