Definition of "endorphin" [endorphin]

• Any of a group of peptide hormones that bind to opiate receptors and are found mainly in the brain. Endorphins reduce the sensation of pain and affect emotions. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Therefore, although it was unknown to us at the time, the term endorphin was no longer useful as a generic term as I had proposed."
• "Avram liked it, and immediately wrote a circular letter to all of the officers and to some of the more distinguished members of the International Narcotic Research Club who were present at the meeting, asking them if they would accept the name endorphin."
• "I’m delighted that the term endorphin is in the Index Medicus, and that one of my names stuck."