attenuate vs shorten

attenuate

verb
  • To reduce in size, force, value, amount, or degree. 

  • To reduce the amplitude of an electrical, radio, or optical signal. 

  • To weaken. 

  • To become thin or fine; to grow less. 

  • To rarefy. 

  • (of a beer) To become less dense as a result of the conversion of sugar to alcohol. 

  • To reduce the virulence of a bacterium or virus. 

  • To make thinner, as by physically reshaping, starving, or decaying. 

adj
  • Gradually tapering into a petiole-like extension toward the base. 

shorten

verb
  • 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 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 attenuate and shorten occurred in a corpus of books? (source: Google Ngram Viewer )