ganglion

noun

gan·​gli·​on ˈgaŋ-glē-ən 

plural ganglia ˈgaŋ-glē-ə  also ganglions

1

: a small cystic tumor connected either with a joint membrane or tendon sheath

2

a

: a mass of nerve tissue containing cell bodies of neurons external to the brain or spinal cord

also : nucleus sense 2b

b

: something likened to a nerve ganglion

a ganglion of cables and wires

ganglionated

ˈgaŋ-glē-ə-ˌnā-təd 

adjective

ganglionic

ˌgaŋ-glē-ˈä-nik 

adjective

Examples of ganglion in a Sentence

Recent Examples on the Web

Our bodies could then invest the surplus energy this saved into ganglia rather than guts, into frontal lobes instead of food. — Big Think, 22 Apr. 2026

Nerve blocks, which pinpoint groups of nerves (a plexus or ganglion), can be administered to block pain receptors and reset function. — Dr. Patricia Richard, Hartford Courant, 14 Apr. 2026

More specifically, each segment of a cockroach’s body has its own dedicated ganglion that’s capable of controlling local reflexes and motor patterns. — Scott Travers, Forbes.com, 6 Feb. 2026

Glaucoma remains a leading cause of blindness worldwide, and while treatments often focus on lowering intraocular pressure, damage to retinal ganglion cells can continue even when pressure is controlled. — Neetika Walter, Interesting Engineering, 4 Feb. 2026

Word History

Etymology

borrowed from Latin, borrowed from Greek ganglíon "tumor on a tendon, mass of nerve tissue (thought to resemble such tumors)," of obscure origin

First Known Use

1597, in the meaning defined at sense 1

Phrases Containing ganglion

• basal ganglion
• dorsal root ganglion
• spinal ganglion

Rhymes for ganglion

• anton
• argon
• axon
• baronne
• baryon
• baton
• boron
• buisson
• bygone
• capon
• cardon
• chiffon

Kids Definition

ganglion

noun

gan·​gli·​on ˈgaŋ-glē-ən 

plural ganglia -glē-ə  also ganglions

: a mass of nerve tissue lying outside the brain or spinal cord and containing neurons

also : nucleus sense c

ganglionic

ˌgaŋ-glē-ˈän-ik 

adjective

Medical Definition

ganglion

noun

gan·​gli·​on ˈgaŋ-glē-ən 

plural ganglia -glē-ə  also ganglions

1

: a small cystic tumor (as on the back of the wrist) containing viscid fluid and connected either with a joint membrane or tendon sheath

2

a

: a mass of nerve tissue containing cell bodies of neurons that is located outside the central nervous system and forms an enlargement upon a nerve or upon two or more nerves at their point of junction or separation

b

: a mass of gray matter within the brain or spinal cord : nucleus sense 2 see basal ganglion