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

empair \empair"\, v. t.
   to impair. obs. --spenser.
   1913 webster

Empair >> E Words
Empair, definition of term: Empair
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