THC is the abbreviation tetrahydrocannabidiol: the active cannabinoid present in the cannabis plant.
This compound is the main psychoactive component of the cannabis plant. It is one of the three cannabinoids that is scheduled by the UN Convention on Psychotropic Substances as Schedule II in 1991.
THC is a lipid of the cannabis plant that is assumed to take part in the plant’s self-defense against insects, parasites, UV rays, and environmental stress.
A pharmaceutical form of THC called dronabinol has been approved by the FDA to be used as an appetite stimulant for AIDS patients and also as an antiemetic for people undergoing chemotherapy.