pineal gland
noun
variants
or less commonly pineal
or pineal body
or pineal organ
: a small, typically cone-shaped structure of the brain that arises from the roof of the third ventricle, is enclosed by the pia mater, and functions primarily as an endocrine gland secreting melatonin
Note: The pineal gland varies in morphological complexity, and in some nonmammalian vertebrates (such as various reptiles) may serve a photoreceptive function.
Examples of pineal gland in a Sentence
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Melatonin is a hormone made by our bodies' pineal gland that helps regulate our circadian rhythms, the natural patterns our bodies experience in a 24-hour cycle.
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Michael Franco, New Atlas, 4 Nov. 2024
Melatonin is a hormone produced in the pineal gland that regulates the sleep-wake cycle and is an antioxidant.18 Melatonin supplements are taken by some people for sleep problems and jet lag.
—Heather Jones, Verywell Health, 1 Aug. 2024
Melatonin is a hormone produced in the brain’s pineal gland that helps maintain our circadian rhythm—the 24-hour internal clock that regulates our sleep/wake cycles.
—Margaret Osborne, Smithsonian Magazine, 18 Dec. 2023
Part of the problem, said Khan, is the disruption of production of melatonin, a naturally occurring hormone that is secreted by the pineal gland in response to darkness.
—Cara Lynn Shultz, Peoplemag, 28 Aug. 2023
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Michael Franco, New Atlas, 4 Nov. 2024
Melatonin is a hormone produced in the pineal gland that regulates the sleep-wake cycle and is an antioxidant.18 Melatonin supplements are taken by some people for sleep problems and jet lag.
—Heather Jones, Verywell Health, 1 Aug. 2024
Melatonin is a hormone produced in the brain’s pineal gland that helps maintain our circadian rhythm—the 24-hour internal clock that regulates our sleep/wake cycles.
—Margaret Osborne, Smithsonian Magazine, 18 Dec. 2023
Part of the problem, said Khan, is the disruption of production of melatonin, a naturally occurring hormone that is secreted by the pineal gland in response to darkness.
—Cara Lynn Shultz, Peoplemag, 28 Aug. 2023
See all Example Sentences for pineal gland
Dictionary Entries Near pineal gland
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“Pineal gland.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pineal%20gland. Accessed 23 Nov. 2024.
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