midbrain

noun

mid·​brain ˈmid-ˌbrān How to pronounce midbrain (audio)
: the middle of the three primary divisions of the developing vertebrate brain or the corresponding part of the adult brain between the forebrain and hindbrain that includes the tectum, tegmentum, and substantia nigra

called also mesencephalon

see brain illustration

Examples of midbrain in a Sentence

Recent Examples on the Web
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
And because the growth was in his midbrain stem, there was no way to remove the tumor, said his mom, Huifan Chan. Jason Mastrodonato, The Mercury News, 10 Aug. 2024 Dopamine neurons receive inputs from a large swath of the brain: your sensory, motor, and limbic systems all send information to the midbrain. Celia Ford, Vox, 22 May 2024 Parallel research into Parkinson’s disease led to a breakthrough: Neurologists realized the disease’s characteristic tremors and muscle stiffness were tied to the loss of dopamine-producing cells in a part of the midbrain that controls movement. Celia Ford, Vox, 22 May 2024 There are three basic units of an vertebrate brain–the midbrain, forebrain, and the hindbrain. Laura Baisas, Popular Science, 22 Feb. 2024 See all Example Sentences for midbrain 

Word History

First Known Use

1864, in the meaning defined above

Time Traveler
The first known use of midbrain was in 1864

Dictionary Entries Near midbrain

Cite this Entry

“Midbrain.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/midbrain. Accessed 5 Nov. 2024.

Kids Definition

midbrain

noun
mid·​brain ˈmid-ˌbrān How to pronounce midbrain (audio)
: the middle division of the three primary divisions of the developing brain of a vertebrate animal or the parts of the adult brain that develop from it that contains the optic lobes and is situated between the forebrain and the hindbrain

Medical Definition

midbrain

noun
mid·​brain ˈmid-ˌbrān How to pronounce midbrain (audio)
: the middle division of the three primary divisions of the developing vertebrate brain or the corresponding part of the adult brain that includes a ventral part containing the cerebral peduncles and a dorsal tectum containing the corpora quadrigemina and that surrounds the aqueduct of Sylvius connecting the third and fourth ventricles

called also mesencephalon

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