melatonin
noun
mel·a·to·nin
ˌme-lə-ˈtō-nən 
: a vertebrate hormone that is derived from serotonin, is secreted by the pineal gland especially in response to darkness, and has been linked to the regulation of circadian rhythms
Examples of melatonin in a Sentence
Recent Examples on the Web
The new study highlights that drinking coffee in the afternoon can disrupt circadian rhythms, which reduces melatonin production.
—
Stephanie Brown, Verywell Health, 18 Jan. 2025
Authorities have accused the women of giving excessive amounts of medication to children at the day care, dosing them with Benadryl and melatonin before their naps.
—Michael Gfoeller and David H. Rundell, Newsweek, 16 Jan. 2025
They’re packed with tyramine and histamines, which interfere with melatonin production—your body’s natural sleep hormone.
—Bryan Robinson, Forbes, 7 Dec. 2024
Researchers believe magnesium may play a small role in the natural creation of melatonin, a hormone that helps regulate your sleep cycle.
—Kirstyn Hill, Pharmd, Mph, Health, 21 Jan. 2025
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Stephanie Brown, Verywell Health, 18 Jan. 2025
Authorities have accused the women of giving excessive amounts of medication to children at the day care, dosing them with Benadryl and melatonin before their naps.
—Michael Gfoeller and David H. Rundell, Newsweek, 16 Jan. 2025
They’re packed with tyramine and histamines, which interfere with melatonin production—your body’s natural sleep hormone.
—Bryan Robinson, Forbes, 7 Dec. 2024
Researchers believe magnesium may play a small role in the natural creation of melatonin, a hormone that helps regulate your sleep cycle.
—Kirstyn Hill, Pharmd, Mph, Health, 21 Jan. 2025
See all Example Sentences for melatonin
Dictionary Entries Near melatonin
Cite this Entry
“Melatonin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/melatonin. Accessed 11 Feb. 2025.
Copy CitationKids Definition
melatonin
noun
mel·a·to·nin
ˌmel-ə-ˈtō-nən
: a hormone that is secreted by the pineal gland especially in response to darkness and has been linked to the regulation of bodily functions or activities (as sleep) that occur in approximately 24 hour cycles
Medical Definition
melatonin
noun
mel·a·to·nin
ˌmel-ə-ˈtō-nən
: a vertebrate hormone C13H16N2O2 that is derived from serotonin, is secreted by the pineal gland especially in response to darkness, and has been linked to the regulation of circadian rhythms
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