[1] : The Collaborative International Dictionary of English v.0.48

shorten \short"en\, v. t. imp.  p. p. shortened ?; p. pr. 
   vb. n. shortening. see short, a.
   1. to make short or shorter in measure, extent, or time; as,
      to shorten distance; to shorten a road; to shorten days of
      calamity.
      1913 webster

   2. to reduce or diminish in amount, quantity, or extent; to
      lessen; to abridge; to curtail; to contract; as, to
      shorten work, an allowance of food, etc.
      1913 webster

            here, where the subject is so fruitful, i am
            shortened by my chain.                --dryden.
      1913 webster

   3. to make deficient as to; to deprive; -- with of.
      1913 webster

            spoiled of his nose, and shortened of his ears.
                                                  --dryden.
      1913 webster

   4. to make short or friable, as pastry, with butter, lard,
      pot liquor, or the like.
      1913 webster

   to shorten a rope naut., to take in the slack of it.

   to shorten sail naut., to reduce sail by taking it in.
      1913 webster
see also:
shortened ? shortening short to shorten a rope to shorten sail 

[2] : The Collaborative International Dictionary of English v.0.48

shorten \short"en\, v. i.
   to become short or shorter; as, the day shortens in northern
   latitudes from june to december; a metallic rod shortens by
   cold.
   1913 webster

[3] : WordNet (r) 2.0

shorten
     v 1: make shorter than originally intended; reduce or retrench in
          length or duration; "he shortened his trip due to
          illness" ant: lengthen
     2: reduce in scope while retaining essential elements; "the
        manuscript must be shortened" syn: abridge, foreshorten,
         abbreviate, cut, contract, reduce ant: elaborate
     3: make short or shorter; "shorten the skirt"; "shorten the
        rope by a few inches"
     4: become short or shorter; "in winter, the days shorten" ant:
         lengthen
     5: edit by omitting or modifying parts considered indelicate;
        "bowdlerize a novel" syn: bowdlerize, bowdlerise, expurgate,
         castrate
see also:
lengthen abridge foreshorten abbreviate cut contract 
reduce elaborate bowdlerize bowdlerise expurgate 
castrate 

[4] : Moby Thesaurus II by Grady Ward, 1.0

121 moby thesaurus words for "shorten":
   abate, abbreviate, abrade, abridge, abstract, bate, be telegraphic,
   bob, bobtail, boil down, brief, capsule, capsulize, circumscribe,
   clip, coarct, compact, compress, concentrate, condense,
   consolidate, constrict, constringe, contract, cramp, crop, curtail,
   cut, cut back, cut down, cut off short, cut short, damp, dampen,
   decrease, deduct, deflate, depreciate, depress, derogate, detract,
   digest, diminish, disparage, dock, downgrade, drain, draw, draw in,
   draw together, eat away, elide, epitomize, erode, excerpt, extract,
   file away, foreshorten, hem, impair, knit, leach, lessen, lower,
   minify, minimize, mow, narrow, nip, nutshell, outline, pare, poll,
   pollard, prune, pucker, pucker up, purify, purse, reap, recap,
   recapitulate, reduce, refine, remove, retrench, roll back,
   rub away, scale down, shave, shear, shrink, simplify, sketch,
   sketch out, slash, snub, solidify, step down, strangle,
   strangulate, stunt, subduct, subtract, sum up, summarize,
   synopsize, take away, take from, take in, telescope, thin,
   thin out, trim, truncate, tune down, waste no words, wear away,
   weed, withdraw, wrinkle

[5] : The Free On-line Dictionary of Computing (27 SEP 03)

shorten
     
         a form of lossless audio
        compression.
     
        details?
     
        2001-12-17
     
     
see also:
lossless audio compression 

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