n. [ Thionine + -ol. ] (Chem.) A red or violet dyestuff having a greenish metallic luster. It is produced artificially, by the chemical dehydration of thionine, as a brown amorphous powder. [ 1913 Webster ]

n. (Chem.) A beautiful fluorescent crystalline substance, intermediate in composition between thionol and thionine. [ 1913 Webster ]