From Longman Dictionary of Contemporary Englishendorphinen‧dor‧phin /enˈdɔːfɪn $ -ˈdɔːr-/ noun [countable usually plural] a chemical produced by your body that reduces pain and can make you feel happier
Examples from the Corpus
endorphin• Naltrexone keeps heroin from activating endorphin receptors, without activating them itself.• They may also enhance endorphin release.Origin endorphin (1900-2000) endo- ( → ENDOCRINE) + morphine 