a highly flammable, colorless or pale-yellow, viscous solution of pyroxylin in a mixture of alcohol and ether: it dries quickly, forming a tough, elastic film, and is used as a protective coating for wounds, in cements, etc.
See collodion in American Heritage Dictionary 4
(kə-lōˈdē-ən)
noun
A highly flammable, colorless or yellowish syrupy solution of pyroxylin, ether, and alcohol, used as an adhesive to close small wounds and hold surgical dressings, in topical medications, and for making photographic plates.