pineal gland

noun
variants: or less commonly pineal or pineal body or pineal organ

Definition of pineal gland

: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.

First Known Use of pineal gland

1712


Medical Dictionary

pineal gland

noun

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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