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

collodion \collo"dion\, n. gr. ? like glue; ko`lla glue + ?
   form. cf. colloid. chem.
   a solution of pyroxylin soluble gun cotton in ether
   containing a varying proportion of alcohol. it is strongly
   adhesive, and is used by surgeons as a coating for wounds;
   but its chief application is as a vehicle for the sensitive
   film in photography.
   1913 webster

   collodion process photog., a process in which a film of
      sensitized collodion is used in preparing the plate for
      taking a picture.

   styptic collodion, collodion containing an astringent, as
      tannin.
      1913 webster
see also:
colloid collodion process styptic collodion 

[2] : WordNet (r) 2.0

collodion
     n : a colorless syrupy solution of pyroxylin in ether and
         alcohol; used as a coating for wounds or photographic
         films

Collodion >> C Words
Collodion, definition of term: Collodion
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