shorten vs truncate

shorten

verb
  • To make shorter; to abbreviate. 

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

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

  • To reduce (sail) by taking it in. 

  • To become shorter. 

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

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

truncate

verb
  • To shorten (something) by, or as if by, cutting part of it off. 

  • To shorten (a decimal number) by removing trailing (or leading) digits. 

  • To replace a corner by a plane (or to make a similar change to a crystal). 

adj
  • Truncated. 

  • Having an abrupt termination. 

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