Word Study
xanthine
CIDE DICTIONARY
xanthine, n. [Gr. xanqo`s yellow.].
A type of purine obtainable as a white microcrystalline powder, C5H4O2N4 , present in muscle tissue, in the liver, spleen, pancreas, and other organs, and also in urine (in small quantities) and some urinary calculi, and in the juices of certain plants; -- so called because it leaves a yellow residue when evaporated to dryness with nitric acid. It is also present in guano. Xanthine is closely related to uric acid. [Webster 1913 Suppl.]
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