The Collaborative International Dictionary of English v.0.48:

Attune \At*tune"\, v. t. [imp. & p. p. Attuned; p. pr. & vb.
   n. Attuning.] [Pref. ad- + tune.]
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   1. To tune or put in tune; to make melodious; to adjust, as
      one sound or musical instrument to another; as, to attune
      the voice to a harp.
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   2. To arrange fitly; to make accordant.
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            Wake to energy each social aim,
            Attuned spontaneous to the will of Jove. --Beattie.
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