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

impairment \impair"ment\, n. oe. enpeirement, of. empirement.
   the state, act, or process of being impaired; injury. "the
   impairment of my health." --dryden.
   1913 webster

[2] : WordNet (r) 2.0

impairment
     n 1: the occurrence of a change for the worse syn: damage, harm
     2: a symptom of reduced quality or strength syn: deterioration
     3: the condition of being unable to perform as a consequence of
        physical or mental unfitness; "reading disability";
        "hearing impairment" syn: disability, disablement, handicap
     4: damage that results in a reduction of strength or quality
     5: the act of making something futile and useless as by
        routine syn: stultification, constipation, deadening
see also:
damage harm deterioration disability disablement handicap 
stultification constipation deadening 

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

72 moby thesaurus words for "impairment":
   adulteration, attrition, curtailment, cut, cutting, damage,
   debilitation, decrease, decrement, defectibility, defectiveness,
   deficiency, depletion, depreciation, derogation, deterioration,
   detraction, detriment, diminution, dip, disadvantage,
   disparagement, drawback, enfeeblement, erroneousness, extraction,
   fallibility, faultiness, flaw, handicap, harm, hurt, immaturity,
   imperfection, impurity, inaccuracy, inadequacy, inadequateness,
   incompleteness, inexactitude, inexactness, injury, lack, lessening,
   liability, loss, loss of ground, marring, mediocrity, mischief,
   patchiness, prejudice, reduction, remission, retraction,
   retrenchment, shortage, shortcoming, shortening, shrinkage,
   sketchiness, step backward, truncation, undermining, undevelopment,
   unevenness, unperfectedness, unsoundness, vitiation, want,
   weakening, worsening

Impairment >> I Words
Impairment, definition of term: Impairment
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