shorten vs tug

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). 

tug

verb
  • To pull or drag with great effort. 

  • To masturbate. 

  • To tow by tugboat. 

  • To pull hard repeatedly. 

noun
  • A dog toy consisting of a rope, often with a knot in it. 

  • A trace, or drawing strap, of a harness. 

  • A tugboat. 

  • An iron hook of a hoisting tub, to which a tackle is affixed. 

  • A sudden powerful pull. 

  • An act of male masturbation. 

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