[ noun ] a resin obtained from the hemp plant; thought to be the active narcotic agent in marijuana <noun.substance>
Cannabin \Can"na*bin\, n. (Chem.) A poisonous resin extracted from hemp ({Cannabis sativa}, variety Indica). The euphoric and narcotic effects of hasheesh are due to this resin; the active ingredient is tetrahydrocannabinol, THC. See {Cannabis Indica}, below. [1913 Webster +PJC]