opioid

== English == === Etymology === Attested 1963; from opium +‎ -oid, to distinguish from opiate. === Pronunciation === (UK) IPA(key): /ˈəʊpiɔɪd/ === Noun === opioid (plural opioids) A substance that has effects similar to opium: (physiology) Any of the natural substances, such as an endorphin, released in the body in response to pain; an endogenous opioid. (pharmacology) Any of a group of synthetic compounds that exhibit similarities to the opium alkaloids that occur in nature. Hyponym: opiate ==== Derived terms ==== ==== Translations ====