A chemical agent that induces stupor, coma, or insensibility to pain. The term usually refers to opiates or opioids, which are called narcotic analgesics. In common parlance and legal usage, it is often used imprecisely to mean illicit drugs, irrespective of their pharmacology. For example, narcotics control legislation in Canada, USA, and certain other countries includes cocaine and cannabis as well as opioids (see also conventions, international drug). Because of this variation in usage, the term is best replaced by one with a more specific meaning (e.g. opioid).
• Narcotic analgesic
A type of analgesic acting on the central nervous system rather than on peripheral nerves. Many opioids (e.g. heroin/diamorphine) are typical narcotic analgesics. (EMCDDA drug profiles glossary)