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

alteration \al`tera"tion\, n. cf. f. alt'eration.
   1. the act of altering or making different.
      1913 webster

            alteration, though it be from worse to better, hath
            in it incoveniences.                  --hooker.
      1913 webster

   2. the state of being altered; a change made in the form or
      nature of a thing; changed condition.
      1913 webster

            ere long might perceive
            strange alteration in me.             --milton.
      1913 webster

            appius claudius admitted to the senate the sons of
            those who had been slaves; by which, and succeeding
            alterations, that council degenerated into a most
            corrupt.                              --swift.
      1913 webster

[2] : WordNet (r) 2.0

alteration
     n 1: an event that occurs when something passes from one state or
          phase to another; "the change was intended to increase
          sales"; "this storm is certainly a change for the
          worse"; "the neighborhood had undergone few
          modifications since his last visit years ago" syn: change,
           modification
     2: the act of making something different as e.g. the size of a
        garment syn: modification, adjustment
     3: the act of revising or altering involving reconsideration
        and modification; "it would require a drastic revision of
        his opinion" syn: revision
see also:
change modification adjustment revision 

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

94 moby thesaurus words for "alteration":
   about-face, accommodation, adaptation, adjustment, amelioration,
   analysis, anatomization, apostasy, atomization, betterment, break,
   change, change of heart, changeableness, changeover,
   constructive change, continuity, conversion, defection,
   degeneration, degenerative change, demarcation, desynonymization,
   deterioration, deviation, difference, differencing,
   differentiation, discontinuity, discrimination, disequalization,
   disjunction, distinction, distinguishment, divergence,
   diversification, diversion, diversity, division, fitting,
   flip-flop, fluctuation, gradual change, improvement,
   individualization, individuation, melioration, metamorphosis,
   mitigation, modification, modulation, mutation, overthrow,
   particularization, passage, personalization, qualification,
   radical change, re-creation, realignment, redesign, reform,
   reformation, remaking, renewal, reshaping, restructuring, reversal,
   revision, revival, revivification, revolution, segregation,
   separation, severalization, severance, shift, shilly-shally,
   specialization, sudden change, switch, total change,
   transformation, transit, transition, turn, turnabout, upheaval,
   vacillation, variation, variety, violent change, wavering,
   worsening

Alteration >> A Words
Alteration, definition of term: Alteration
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