Agonist

A drug or substance that binds to a receptor inside a cell or on its surface and causes the same action as the substance that normally binds to the receptor. For instance, the active compounds tetrahydrocannabinol (THC), cannabidiol, cannabinol, and tetrahydrocannabivarin in the plant C. Sativa are physiological and psychoactive compounds. These active compounds are cannabinoid receptor agonists, meaning they stimulate the cannabinoid receptor to enhance its effect.