rotten stone

Rotten \Rot"ten\, a. [Icel. rotinn; akin to Sw. rutten, Dan.
   radden. See {Rot}.]
   Having rotted; putrid; decayed; as, a rotten apple; rotten
   meat. Hence:
   (a) Offensive to the smell; fetid; disgusting.
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             You common cry of curs! whose breath I hate
             As reek of the rotten fens.          --Shak.
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   (b) Not firm or trusty; unsound; defective; treacherous;
       unsafe; as, a rotten plank, bone, stone. "The deepness of
       the rotten way." --Knolles.
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   {Rotten borough}. See under {Borough}.

   {Rotten stone} (Min.), a soft stone, called also Tripoli
      (from the country from which it was formerly brought),
      used in all sorts of finer grinding and polishing in the
      arts, and for cleaning metallic substances. The name is
      also given to other friable siliceous stones applied to
      like uses.
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   Syn: Putrefied; decayed; carious; defective; unsound;
        corrupt; deceitful; treacherous.
        [1913 Webster] -- {Rot"ten*ly}, adv. -- {Rot"ten*ness},
        n.
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