untune

from WordNet (r) 3.0 (2006)

untune
    v 1: cause to lose one's composure [syn: {upset}, {discompose},
         {untune}, {disconcert}, {discomfit}]
    2: cause to be out of tune; "Don't untune that string!" [ant:
       {tune}, {tune up}]

from The Collaborative International Dictionary of English v.0.48

Untune \Un*tune"\, v. t. [1st pref. un- + tune.]
   To make incapable of harmony, or of harmonious action; to put
   out of tune. --Shak.
   [1913 Webster]

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