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pineal gland

American  

noun

  1. a small, cone-shaped endocrine organ in the posterior forebrain, secreting melatonin and involved in biorhythms and gonadal development.


pineal gland British  

noun

  1. Technical names: epiphysis.   epiphysis cerebri.  a pea-sized organ in the brain, situated beneath the posterior part of the corpus callosum, that secretes melatonin into the bloodstream

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

pineal gland Scientific  
  1. A small gland located near the brain and primarily involved in the production and secretion of the hormone melatonin, which regulates circadian rhythms in many animals, including humans.


Etymology

Origin of pineal gland

First recorded in 1705–15

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Melatonin is a hormone produced by the pineal gland that regulates the body's sleep-wake cycle.

From Science Daily

But in the case of cysts of the pineal gland, there is a large amount of information on the web which prompts patients to seek surgery for minor and often unrelated symptoms.

From BBC

Melatonin is produced naturally in the pineal gland to signal the body that it is time to sleep and regulate its circadian rhythm -- the physiological cycle over a 24-hour period.

From Science Daily

These supplements, including sugary gummies, typically offer much higher doses than what the pineal gland produces to help shift circadian rhythm to night mode.

From Scientific American

Melatonin is a naturally occurring hormone produced by the pineal gland, a small structure at the center of the brain.

From Washington Post