orexin

noun
orex·​in | \ ə-ˈrek-sən How to pronounce orexin (audio) \

Medical Definition of orexin

: 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

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Dictionary Entries Near orexin

Oretic

orexin

orexis

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Cite this Entry

“Orexin.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/orexin. Accessed 5 Jul. 2022.

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