The Collaborative International Dictionary
lupuline
Lupulin \Lu"pu*lin\, n. [Cf. F. lupulin. See Lupuline.]
(Chem.) A bitter principle extracted from hops.
The fine yellow resinous powder found upon the strobiles or fruit of hops, and containing this bitter principle.
Wiktionary
lupuline
n. (context organic compound English) An alkaloid extracted from hops.