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Webster 1913 Edition
Parillin
Pa-ril′lin
,Noun.
 [Shortened fr. 
sarsaparillin
.] (Chem.) 
A glucoside resembling saponin, found in the root of sarsaparilla, smilax, etc., and extracted as a bitter white crystalline substance; – called also 
smilacin
, sarsaparilla saponin
, and sarsaparillin
.