under penalty of

Penalty \Pe"nal*ty\, n.; pl. {Penalties}. [F. p['e]nalit['e].
   See {Penal}.]
   1. Penal retribution; punishment for crime or offense; the
      suffering in person or property which is annexed by law or
      judicial decision to the commission of a crime, offense,
      or trespass.
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            Death is the penalty imposed.         --Milton.
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   2. The suffering, or the sum to be forfeited, to which a
      person subjects himself by covenant or agreement, in case
      of nonfulfillment of stipulations; forfeiture; fine.
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            The penalty and forfeit of my bond.   --Shak.
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   3. A handicap. [Sporting Cant]
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   Note: The term penalty is in law mostly applied to a
         pecuniary punishment.
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   {Bill of pains and penalties}. See under {Bill}.

   {On penalty of}, or {Under penalty of}, on pain of; with
      exposure to the penalty of, in case of transgression.
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