To throw down the gauntlet

Gauntlet \Gaunt"let\, n. [F. gantelet, dim. of gant glove, LL.
   wantus, of Teutonic origin; cf. D. want, Sw. & Dan. vante,
   Icel. v["o]ttr, for vantr.]
   1. A glove of such material that it defends the hand from
      wounds.
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   Note: The gauntlet of the Middle Ages was sometimes of chain
         mail, sometimes of leather partly covered with plates,
         scales, etc., of metal sewed to it, and, in the 14th
         century, became a glove of small steel plates,
         carefully articulated and covering the whole hand
         except the palm and the inside of the fingers.
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   2. A long glove, covering the wrist.
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   3. (Naut.) A rope on which hammocks or clothes are hung for
      drying.
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   {To take up the gauntlet}, to accept a challenge.

   {To throw down the gauntlet}, to offer or send a challenge.
      The gauntlet or glove was thrown down by the knight
      challenging, and was taken up by the one who accepted the
      challenge; -- hence the phrases.
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