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

contraction \contrac"tion\, n. l. contractio: cf. f.
   contraction.
   1. the act or process of contracting, shortening, or
      shrinking; the state of being contracted; as, contraction
      of the heart, of the pupil of the eye, or of a tendon; the
      contraction produced by cold.
      1913 webster

   2. math. the process of shortening an operation.
      1913 webster

   3. the act of incurring or becoming subject to, as
      liabilities, obligation, debts, etc.; the process of
      becoming subject to; as, the contraction of a disease.
      1913 webster

   4. something contracted or abbreviated, as a word or phrase;
      -- as, plenipo for plenipotentiary; crim. con. for
      criminal conversation, etc.
      1913 webster

   5. gram. the shortening of a word, or of two words, by the
      omission of a letter or letters, or by reducing two or
      more vowels or syllables to one; as, ne'er for never;
      can't for can not; don't for do not; it's for it is.
      1913 webster

   6. a marriage contract. obs. --shak.
      1913 webster

[2] : WordNet (r) 2.0

contraction
     n 1: physiology a shortening or tensing of a part or organ
          especially of a muscle or muscle fiber syn: muscular
          contraction, muscle contraction
     2: the process or result of becoming smaller or pressed
        together; "the contraction of a gas on cooling" syn: compression,
         condensation
     3: a word formed from two or more words by omitting or
        combining some sounds; "`won't' is a contraction of `will
        not'"; "`o'clock' is a contraction of `of the clock'"
     4: the act of decreasing something in size or volume or
        quantity or scope ant: expansion
see also:
muscular contraction muscle contraction compression condensation expansion 

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

57 moby thesaurus words for "contraction":
   speedwriting, abatement, abbreviation, abridgment, alleviation,
   apocope, aposiopesis, attenuation, brachygraphy, clipping,
   coarctation, constriction, crasis, cutting, dampening, damping,
   decrease, decrement, decrescence, deduction, deflation,
   depreciation, depression, diminishment, diminution, dying,
   dying off, elision, ellipsis, extenuation, fade-out, languishment,
   lessening, letup, lowering, miniaturization, mitigation, narrowing,
   phonography, pruning, reduction, relaxation, sagging, scaling down,
   shortening, shorthand, simplicity, stenography, stricture,
   subtraction, syncope, syneresis, tachygraphy, taper, tapering,
   truncation, weakening

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

contraction
     
        reduction
     
     
see also:
reduction 

[5] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

contraction. an abbreviation; a mode of writing or printing by which some of 
the letters of a word are omitted. see abbreviations. 

Contraction >> C Words
Contraction, definition of term: Contraction
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