thalamus

American  

[thal-uh-muhs] / ˈθæl ə məs /

noun

plural

thalami

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, θəˈlæmɪk /

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 /

plural

thalami

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

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

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

Using functional ultrasound imaging and electrical recordings, the researchers identified the mediodorsal thalamus as the brain region most affected by the mutation.

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 researchers observed that nerve fibers from the thalamus grew toward the cortex, while cortical fibers extended toward the thalamus.

From Science Daily • Jan. 7, 2026

Professor Fumitaka Osakada, graduate student Masatoshi Nishimura, and their colleagues at the Graduate School of Pharmaceutical Sciences at Nagoya University developed assembloids that model interactions between the thalamus and the cortex.

From Science Daily • Jan. 7, 2026

Elongation of the thalamus, placenta, &c.—In some plants, as in Magnolia or Myosurus, the thalamus becomes much elongated, and bears the carpels disposed spirally around it.

From Vegetable Teratology An Account of the Principal Deviations from the Usual Construction of Plants by Masters, Maxwell T.