Xanthin

1. n. One of the gaseous or volatile decomposition products of the xanthates, and probably identical with carbon disulphide.
2. n. A crystalline nitrogenous body closely related to both uric acid and hypoxanthin, present in muscle tissue, and occasionally found in the urine and in some urinary calculi. It is also present in guano. So called from the yellow color of certain of its salts (nitrates).
3. n. A yellow insoluble coloring matter extracted from yellow flowers; specifically, the coloring matter of madder.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.