Polyporus igniarius

Touchwood \Touch"wood`\, n. [Probably for tachwood; OE. tache
   tinder (of uncertain origin) + wood.]
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   1. Wood so decayed as to serve for tinder; spunk, or punk.
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   2. Dried fungi used as tinder; especially, the {Polyporus
      igniarius}.
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Agaric \Ag"a*ric\ (?; 277), n. [L. agaricum, Gr. ?, said to be
   fr. Agara, a town in Sarmatia.]
   1. (Bot.) A fungus of the genus {Agaricus}, of many species,
      of which the common mushroom is an example.
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   2. An old name for several species of {Polyporus}, corky
      fungi growing on decaying wood.
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   Note: The "female agaric" ({Polyporus officinalis}) was
         renowned as a cathartic; the "male agaric" ({Polyporus
         igniarius}) is used for preparing touchwood, called
         punk or German tinder.
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   {Agaric mineral}, a light, chalky deposit of carbonate of
      lime, sometimes called {rock milk}, formed in caverns or
      fissures of limestone.
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