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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Using Pineal Glad Meditation Pineal gland meditation is a breathing technique associated with activating the pineal gland, a small gland in your brain that produces melatonin, a hormone that regulates your sleep and wakefulness.
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Sherri Gordon, Health, 12 May 2025
Melatonin is a hormone the pineal gland produces that is essential for regulating sleep.
—Elizabeth Barnes, Verywell Health, 19 Mar. 2025
This wellness trend is all about, well, maximizing your sleep every night with practices like mouth taping, pineal gland meditation, sleeping in a cold room, and more.
—Sherri Gordon, Health, 12 May 2025
Your pineal gland controls your release of melatonin throughout the day.
—Elizabeth Barnes, Verywell Health, 19 Mar. 2025
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Sherri Gordon, Health, 12 May 2025
Melatonin is a hormone the pineal gland produces that is essential for regulating sleep.
—Elizabeth Barnes, Verywell Health, 19 Mar. 2025
This wellness trend is all about, well, maximizing your sleep every night with practices like mouth taping, pineal gland meditation, sleeping in a cold room, and more.
—Sherri Gordon, Health, 12 May 2025
Your pineal gland controls your release of melatonin throughout the day.
—Elizabeth Barnes, Verywell Health, 19 Mar. 2025
See All Example Sentences for pineal gland
Cite this Entry
“Pineal gland.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pineal%20gland. Accessed 2 Jun. 2025.
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