Main Entry: en·dor·phin

Pronunciation: \en-ˈdȯr-fən\

Function: noun

Etymology: International Scientific Vocabulary endogenous + metersorphine

Date: 1976

: any of a group of endogenous peptides (as enkephalin) found especially in the brain that bind chiefly to opiate receptors and produce some pharmacological effects (as pain relief) like those of opiates; specifically : beta-endorphin