orex·​in ə-ˈrek-sən How to pronounce orexin (audio)
: either of two neuropeptides ( orexin A and orexin B ) that are produced in the hypothalamus and play a role in regulating wakefulness and food intake
Scientists have known for almost a decade that narcolepsy is caused by a dearth of a brain communication chemical called orexin.Laura Sanders, Science News
The new sleep aids block the activity of brain peptides called orexins.Christine Soares, Scientific American

called also hypocretin

Dictionary Entries Near orexin

Cite this Entry

“Orexin.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/orexin. Accessed 14 Jul. 2024.

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