[1] : The Collaborative International Dictionary of English v.0.48

frost \frost\ fro^st; 115, n. oe. frost, forst, as. forst,
   frost. fr. fre'osan to freeze; akin to d. varst, g., ohg.,
   icel., dan.,  sw. frost. root18. see freeze, v. i.
   1. the act of freezing; -- applied chiefly to the congelation
      of water; congelation of fluids.
      1913 webster

   2. the state or temperature of the air which occasions
      congelation, or the freezing of water; severe cold or
      freezing weather.
      1913 webster

            the third bay comes a frost, a killing frost.
                                                  --shak.
      1913 webster

   3. frozen dew; -- called also hoarfrost or white frost.
      1913 webster

            he scattereth the hoarfrost like ashes. --ps.
                                                  cxlvii. 16.
      1913 webster

   4. coldness or insensibility; severity or rigidity of
      character. r.
      1913 webster

            it was of those moments of intense feeling when the
            frost of the scottish people melts like a snow
            wreath.                               --sir w.
                                                  scott.
      1913 webster

   black frost, cold so intense as to freeze vegetation and
      cause it to turn black, without the formation of
      hoarfrost.

   frost bearer physics, a philosophical instrument
      illustrating the freezing of water in a vacuum; a
      cryophorus.

   frost grape bot., an american grape, with very small,
      acid berries.

   frost lamp, a lamp placed below the oil tube of an argand
      lamp to keep the oil limpid on cold nights; -- used
      especially in lighthouses. --knight.

   frost nail, a nail with a sharp head driven into a horse's
      shoe to keep him from slipping.

   frost smoke, an appearance resembling smoke, caused by
      congelation of vapor in the atmosphere in time of severe
      cold.
      1913 webster

            the brig and the ice round her are covered by a
            strange black
            obscurity: it is the frost smoke of arctic winters.
                                                  --kane.

   frost valve, a valve to drain the portion of a pipe,
      hydrant, pump, etc., where water would be liable to
      freeze.

   jack frost, a popular personification of frost.
      1913 webster
see also:
freeze hoarfrost white frost black frost frost bearer frost grape 
frost lamp frost nail frost smoke frost valve jack frost 

[2] : The Collaborative International Dictionary of English v.0.48

hoarfrost \hoar"frost`\, n.
   the white particles formed by the congelation of dew; white
   frost. written also horefrost. see hoar, a.
   1913 webster

         he scattereth the hoarfrost like ashes.  --ps. cxlvii.
                                                  16.
   1913 webster
see also:
horefrost hoar 

[3] : WordNet (r) 2.0

hoarfrost
     n : ice crystals forming a white deposit especially on objects
         outside syn: frost, hoar, rime
see also:
frost hoar rime 

Hoarfrost >> H Words
Hoarfrost, definition of term: Hoarfrost
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