thalamus

American  

[thal-uh-muhs] / ˈθæl ə məs /

noun

• thalami
  plural

1. Anatomy. the middle part of the diencephalon through which sensory impulses pass to reach the cerebral cortex.

2. Botany. a receptacle or torus.

3. Also called thalamium. an apartment for women in an ancient Greek house.

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thalamus British  

/ ˈθæləməs /

noun

1. either of the two contiguous egg-shaped masses of grey matter at the base of the brain

2. both of these masses considered as a functional unit

3. the receptacle or torus of a flower

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thalamus Scientific  

/ thăl′ə-məs /

• thalami
  plural

1. The part of the vertebrate brain that lies at the rear of the forebrain. It relays sensory information to the cerebral cortex and regulates the perception of touch, pain, and temperature.

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thalamus Cultural  

1. The part of the brain that coordinates nerve impulses relating to the senses of sight, hearing, touch, and taste.

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Other Word Forms

Derived Forms

• postthalamic
  adjective
• subthalamic
  adjective
• thalamic
  adjective
• transthalamic
  adjective
• thalamically
  adverb

Inflected Forms

Nouns

• thalami
  plural

Etymology

Origin of thalamus

1695–1705; < New Latin; Latin: bedroom < Greek thálamos

Compare meaning

How does thalamus compare to similar and commonly confused words? Explore the most common comparisons:

• hypothalamus vs. thalamus

Explanation

The thalamus is an egg-shaped mass of gray matter that's located in the middle of the brain. The thalamus is responsible for transmitting sensory signals between different parts of the brain. The thalamus plays a crucial role in regulating consciousness, sleep, and alertness by directing sensory information to different parts of the brain. It receives input from sensory organs such as the eyes, ears, and skin and then relays that information to other regions of the brain for further processing. This important structure, which is located near the center of the brain, gets its name from the Greek word thalamos, which means "inner chamber."

Example Sentences

See Examples For:

thalamus thalami

Neurons in the mediodorsal thalamus appeared to track changes in the value of different choices.

From Science Daily ● Apr. 3, 2026

However, how the thalamus and cortex interact during circuit formation in the human brain has remained largely unknown.

From Science Daily ● Jan. 7, 2026

The cortical tissue connected to the thalamus showed signs of greater maturity, indicating that thalamus cortex communication promotes cortical growth and development.

From Science Daily ● Jan. 7, 2026

Synchronized activity was seen in PT and CT neurons, both of which send signals back to the thalamus.

From Science Daily ● Jan. 7, 2026

The posterior knob-like extremity of the thalamus is called the pulvinar; this, as well as the two corpora geniculata and the superior corpus quadrigeminum, is connected with the optic tract.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Slice 4 "Bradford, William" to "Brequigny, Louis" by Various

Their brains are fused together by a neural bridge that connects them at their respective thalami.

From Slate ● Apr. 30, 2018

The two thalami touch in the center in most brains as the massa intermedia, which is surrounded by the third ventricle.

From Textbooks ● Jun. 19, 2013

The thalami are two elongated, ovoid structures on either side of the midline that make contact in the middle.

From Textbooks ● Jun. 19, 2013

The cavity of this ventricle is of small size in the living head, for the inner surfaces of the two thalami are connected together by intermediate grey matter, named the middle or soft commissure.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Slice 4 "Bradford, William" to "Brequigny, Louis" by Various

If the velum interpositum be now carefully raised from before backward, the optic thalami, third ventricle, pineal body and corpora quadrigemina are exposed.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Slice 4 "Bradford, William" to "Brequigny, Louis" by Various