endorphin

noun

en·​dor·​phin en-ˈdȯr-fən 

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

specifically : beta-endorphin

Did you know?

The word endorphin was coined, back when the substances were discovered in the 1970s, by joining pieces of endogenous and morphine, morphine being a narcotic that closely resembles the endorphins and relieves pain in a similar way. Studies suggest that the pain-relieving practice called acupuncture works by releasing endorphins. Endorphins also seem to play an important role in pregnancy. Though much remains to be learned about the endorphins, the general public seems ready to give them credit for any all-natural high.

Examples of endorphin in a Sentence

Recent Examples on the Web

Beyond that, research finds that helping others can reduce stress, increase mood-boosting endorphins and contribute to better self-esteem. —Helen Carefoot, Flow Space, 1 Jan. 2026

Walking decreases stress by releasing endorphins (chemical messengers that can help improve mood). —Team Verywell Health, Verywell Health, 29 Dec. 2025

These actions trigger the release of chemicals such as dopamine and endorphins, which are associated with positive feelings. —Katia Hetter, CNN Money, 21 Dec. 2025

And Britain’s own Action Mental Health organization insists that having a larf releases endorphins and boosts the immune system and mood. —Baz Bamigboye, Deadline, 5 Dec. 2025

Word History

Etymology

International Scientific Vocabulary endogenous + morphine

First Known Use

1976, in the meaning defined above

Phrases Containing endorphin

• beta-endorphin

Rhymes for endorphin

• dextromethorphan
• orphan

Medical Definition

endorphin

noun

en·​dor·​phin en-ˈdȯr-fən 

: any of a group of endogenous peptides (as enkephalin and dynorphin) found especially in the brain that bind chiefly to opiate receptors and produce some of the same pharmacological effects (as pain relief) as those of opiates

specifically : beta-endorphin