midbrain
noun
mid·brain
ˈmid-ˌbrān 
: 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 illustrationExamples of midbrain in a Sentence
Recent Examples on the Web
The ventral tegmental area (VTA) in the midbrain is the primary region responsible for producing dopamine.
—
Jennifer Borresen, USA TODAY, 14 Feb. 2025
Each has a spinal cord, which controls reflex behaviors; a brain stem, which controls autonomic behaviors such as breathing and heart rate; and a midbrain, which controls emotions and basic behaviors.
—IEEE Spectrum, 2 June 2017
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
See All Example Sentences for midbrain
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Jennifer Borresen, USA TODAY, 14 Feb. 2025
Each has a spinal cord, which controls reflex behaviors; a brain stem, which controls autonomic behaviors such as breathing and heart rate; and a midbrain, which controls emotions and basic behaviors.
—IEEE Spectrum, 2 June 2017
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
See All Example Sentences for midbrain
Cite this Entry
“Midbrain.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/midbrain. Accessed 1 Mar. 2025.
Copy CitationKids Definition
midbrain
noun
mid·brain
ˈmid-ˌbrān
: 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
: 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
Love words? Need even more definitions?
Merriam-Webster unabridged
Share