The Collaborative International Dictionary of English v.0.48:

Identity \I*den"ti*ty\, n.; pl. Identities. [F. identit['e],
   LL. identitas, fr. L. idem the same, from the root of is he,
   that; cf. Skr. idam this. Cf. Item.]
   1. The state or quality of being identical, or the same;
      sameness.
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            Identity is a relation between our cognitions of a
            thing, not between things themselves. --Sir W.
                                                  Hamilton.
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   2. The condition of being the same with something described
      or asserted, or of possessing a character claimed; as, to
      establish the identity of stolen goods.
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   3. (Math.) An identical equation.
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