from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Either of two closely related pentapeptides having opiate qualities and occurring in the brain, spinal cord, and other parts of the body.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Any of a group of pentapeptide endorphins that have opiate-like effects
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. an endorphin having opiate qualities that occurs in the brain and spinal cord and elsewhere
Greek enkephalos, in the head (en-, in; see en in Indo-European roots + kephalē, head; see ghebh-el- in Indo-European roots) + -in.(American Heritage® Dictionary of the English Language, Fourth Edition)