lead on vs shorten

lead on

verb
  • Used other than figuratively or idiomatically: see lead, on. 

  • to mislead, to try to make someone believe a lie. 

  • to encourage with the illusion of a romantic relationship. 

shorten

verb
  • To take in the slack of (a rope). 

  • To reduce or diminish in amount, quantity, or extent; to lessen. 

  • To reduce (sail) by taking it in. 

  • To become shorter. 

  • To make shorter; to abbreviate. 

  • To make short or friable, as pastry, with butter, lard, etc. 

  • To make deficient (as to); to deprive (of). 

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