cocaine

Cocaine is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant. The name comes from "coca" in addition to the alkaloid suffix -ine, forming cocaine. It is both a stimulant of the central nervous system and an appetite suppressant, giving rise to what has been described as a euphoric sense of happiness and increased energy. It is most often used recreationally for this effect. Because of the way it effects the mesolimbic reward pathway, cocaine is addictive. Nevertheless, cocaine is formally used in medicine as a topical anesthetic, specifically in eye, nose and throat surgery.
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n. cocaine, drug used to relieve pain (highly addictive)

n. cocaine, drug used to relieve pain (highly addictive)

(n.)
A powerful alkaloid, C17H21NO4, obtained from the leaves of coca. It is a bitter, white, crystalline substance, and is remarkable for producing local insensibility to pain.