The Collaborative International Dictionary of English v.0.48:

Imparity \Im*par"i*ty\, n. [Pref. im- + parity: cf. F.
   imparit['e].]
   1. Inequality; disparity; disproportion; difference of
      degree, rank, excellence, number, etc. --Milton.
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   2. Lack of comparison, correspondence, or suitableness;
      incongruity.
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            In this region of merely intellectual notion we are
            at once encountered by the imparity of the object
            and the faculty employed upon it.     --I. Taylor.
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   3. Indivisibility into equal parts; oddness. [R.]
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