a bitter, poisonous alkaloid, CHNO, found in seeds of nux vomica and other related plants: used as a lubricant additive and, in medicine, as a local anesthetic
See brucine in American Heritage Dictionary 4
(bro͞oˈsēnˌ, -sĭn)
noun
A poisonous white crystalline alkaloid, C23H26N2O4, derived from the seeds of nux vomica and closely related plants and used to denature alcohol.