Misprision of treason

Misprision \Mis*pri"sion\, n. [LL. misprisio, or OF. mesprison,
   prop., a mistaking, but confused with OF. mespris contempt,
   F. m['e]pris. See 2d {Misprise}, {Misprize}, {Prison}.]
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   1. The act of misprising; misapprehension; misconception;
      mistake. [Archaic] --Fuller.
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            The misprision of this passage has aided in
            fostering the delusive notion.        --Hare.
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   2. Neglect; undervaluing; contempt. [Obs.] --Shak.
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   3. (Law) A neglect, negligence, or contempt.
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   Note: In its larger and older sense it was used to signify
         "every considerable misdemeanor which has not a certain
         name given to it in the law." --Russell.
         In a more modern sense it is applied exclusively to two
         offenses: 
         1.

   {Misprision of treason}, which is omission to notify the
      authorities of an act of treason by a person cognizant
      thereof. --Stephen.
      2.

   {Misprision of felony}, which is a concealment of a felony by
      a person cognizant thereof. --Stephen.
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