The Collaborative International Dictionary
Xanthinine
Xanthinine \Xan"thi*nine\, n. [Gr. xanqo`s yellow + quinine.] (Chem.) A complex nitrogenous substance related to urea and uric acid, produced as a white powder; -- so called because it forms yellow salts, and because its solution forms a blue fluorescence like quinine.
Wiktionary
xanthinine
n. (context obsolete organic chemistry English) A poorly-characterised material, related to urea and uric acid, that forms yellow salts, and exhibits a blue fluorescence