Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Scrabble
  • Spanish Central
  • Learner's Dictionary

pineal gland

noun

Definition of pineal gland

  1. :  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



1712

First Known Use of pineal gland

1712


Medical Dictionary

pineal gland

noun

Medical Definition of pineal gland

  1. :  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




Learn More about pineal gland


Seen and Heard

What made you want to look up pineal gland? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

mysterious, holy, or spiritual

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

lavender-fields-in-france

Which of these is a synonym of caesura?

rebellion torrent megillah interruption
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ