The Collaborative International Dictionary of English v.0.48:

Mistake \Mis*take"\ (m[i^]s*t[=a]k"), n.
   1. An apprehending wrongly; a misconception; a
      misunderstanding; a fault in opinion or judgment; an
      unintentional error of conduct.
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            Infallibility is an absolute security of the
            understanding from all possibility of mistake.
                                                  --Tillotson.
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   2. (Law) Misconception, error, which when non-negligent may
      be ground for rescinding a contract, or for refusing to
      perform it.
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   No mistake, surely; without fail; as, it will happen at the
      appointed time, and no mistake. [Low]
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   Syn: Blunder; error; bull. See Blunder.
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