Wordnet 3.0
NOUN (1)
1.
crystalline oxidation product of the metabolism of nucleoproteins;
precursor of uric acid;
found in many organs and in urine;
The Collaborative International Dictionary of English v.0.48:
Xanthine \Xan"thine\, n. Also Xanthin \Xan"thin\ . [Gr. xanqo`s
yellow.] (Physiol. Chem.)
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.]
WordNet (r) 3.0 (2006):
xanthine
n 1: crystalline oxidation product of the metabolism of
nucleoproteins; precursor of uric acid; found in many
organs and in urine