Definition of pineal gland
: a small usually conical appendage of the brain of all craniate vertebrates that functions primarily as an endocrine gland secreting melatonin and that in a few reptiles has the essential structure of an eye —called also pineal, pineal body, pineal organ
First Known Use of pineal gland
Rhymes with pineal gland
Medical Definition of pineal gland
: a small body that arises from the roof of the third ventricle and is enclosed by the pia mater and that functions primarily as an endocrine gland that produces melatonin—called also pineal, pineal body, pineal organ
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