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

impair \impair"\, v. t. imp.  p. p. impaired; p. pr.  vb.
   n. impairing. written also empair. oe. empeiren,
   enpeiren, of. empeirier, empirier, f. empirer, ll.
   impejorare; l. pref. im- in + pejorare to make worse, fr.
   pejor worse. cf. appair.
   to make worse; to diminish in quantity, value, excellence, or
   strength; to deteriorate; as, to impair health, character,
   the mind, value.
   1913 webster

         time sensibly all things impairs.        --roscommon.
   1913 webster

         in years he seemed, but not impaired by years. --pope.

   syn: to diminish; decrease; injure; weaken; enfeeble;
        debilitate; reduce; debase; deteriorate.
        1913 webster
see also:
impaired impairing empair appair 

[2] : WordNet (r) 2.0

impaired
     adj 1: diminished in strength, quality, or utility; "impaired
            eyesight" ant: unimpaired
     2: mentally or physically unfit syn: afflicted
see also:
unimpaired afflicted 

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

76 moby thesaurus words for "impaired":
   adulterated, aggravated, blemished, broken, burned, burst, busted,
   checked, chipped, cracked, crazed, cut, damaged, defective,
   deficient, deteriorated, embittered, erroneous, exacerbated,
   fallible, faulty, flawed, found wanting, harmed, hurt, immature,
   imperfect, imprecise, impure, in bits, in pieces, in shards,
   inaccurate, inadequate, incomplete, inexact, injured, irritated,
   lacerated, lacking, makeshift, mangled, marred, mediocre, mixed,
   mutilated, not perfect, off, partial, patchy, rent, ruptured,
   scalded, scorched, shattered, short, sketchy, slashed, slit,
   smashed, split, spoiled, sprung, the worse for, torn, undeveloped,
   uneven, unfinished, unperfected, unsound, unthorough, wanting,
   weakened, worse, worse off, worsened

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