ganglion

American  

[gang-glee-uhn] / ˈgæŋ gli ən /

noun

• ganglia,
  plural
• ganglions
  plural

1. Anatomy.

   1. a mass of nerve tissue existing outside the central nervous system.

   2. any of certain masses of gray matter in the brain, as the basal ganglia.

2. Pathology. a cyst or enlargement in connection with the sheath of a tendon, usually at the wrist.

3. a center of intellectual or industrial force, activity, etc.

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ganglion British  

/ ˈɡæŋɡlɪən /

noun

1. an encapsulated collection of nerve-cell bodies, usually located outside the brain and spinal cord

2. any concentration of energy, activity, or strength

3. a cystic tumour on a tendon sheath or joint capsule

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ganglion Scientific  

/ găng′glē-ən /

• ganglia
  plural

1. A compact group of neurons enclosed by connective tissue and having a specific function. In invertebrate animals, pairs of ganglia occur at intervals along the axis of the body, with the forwardmost pair functioning like a brain. In vertebrates, ganglia are usually located outside the brain or spinal cord, where they regulate the functioning of the body's organs and glands as part of the autonomic nervous system.

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Other Word Forms

Derived Forms

• ganglial
  adjective
• gangliar
  adjective
• ganglionic
  adjective

Inflected Forms

Nouns

• ganglia
  plural
• ganglions
  plural

Etymology

Origin of ganglion

1675–85; < Late Latin: a type of swelling < Greek gánglion a tumor under the skin, on or near a tendon

Explanation

In medicine, a ganglion is a cluster of nerve cells. Although it's not related to nerve cells, a harmless but visible lump on the skin is known as a ganglion cyst. It's not uncommon for people to get benign but annoying ganglion cysts on their hands as they age. This use of ganglion goes back to the Greek root meaning "knot, swelling under the skin, or tumor." Ganglion came to mean "nerve cells" in medical terminology by the 17th century (although the cyst meaning also stuck around). Humans have many ganglia in their bodies, including the clusters around our spinal nerves and the basal ganglia in our brains.

Example Sentences

See Examples For:

ganglion ganglia ganglions

If short-wavelength light activates the ganglion cells, they signal to the internal clock that it is daytime.

From Science Daily ● Dec. 22, 2023

In contrast, they found 21 orthotypes of retinal ganglion cells, which exhibit greater variation among species.

From Science Daily ● Dec. 13, 2023

During development, the retinal ganglion cells also generate their own neuronal activity.

From Science Daily ● Sep. 28, 2023

It found people with Parkinson's had a thinner ganglion cell-inner plexiform layer and inner nuclear layer in the eye.

From BBC ● Aug. 22, 2023

You might begin at the local beach, which functions as a sort of ganglion.

From "The Lives of a Cell" by Lewis Thomas

"For decades, Parkinson's has been primarily associated with motor deficits and the basal ganglia," the part of the brain that controls muscle movements, Liu said.

From Science Daily ● Feb. 8, 2026

These overstimulated immune cells then move toward the dorsal root ganglia -- the sensory nerve hubs that link the limbs to the spinal cord -- and release inflammatory compounds that irritate and damage nerves.

From Science Daily ● Nov. 21, 2025

"A previous study showed that the cerebral cortex and the basal ganglia were mostly deactivated under anesthesia, which we also observed, however, in awake states these areas are significantly activated."

From Science Daily ● May 31, 2024

The basal ganglia receives signals from the motor cortex as skaters leap and twirl in the air.

From New York Times ● Mar. 27, 2024

“The reflex-arc response taking place in the upper ganglia of the spinal column requires several microseconds more in the humanoid robot than in a human nervous system.”

From "Do Androids Dream of Electric Sheep?" by Philip K. Dick

They have a brain that’s wrapped around their esophagus, ganglions on every one of their little suckers.

From Slate ● May 31, 2017

Peter and Paul are so busy representing alternate responses to stimuli that they seem ganglions rather than real folks.

From Time Magazine Archive

Simple and sensible though these reforms seemed to outsiders, they cut deep into Yale's vital fabric of traditions, left a mass of supersensitive and unsutured ganglions.

From Time Magazine Archive

The oyster, who has neither head nor brain, has, as his only instrument of action, certain little masses of nervous substance scattered right and left, which are called ganglions.

From The History of a Mouthful of Bread And its effect on the organization of men and animals by Jean Macé

Of course," muttered the shaken aviator, "I'd forgotten a reptile's ganglions will keep on beating for hours, like that shark we killed off Paumotu.

From Astounding Stories, February, 1931 by Harry Bates

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