gan·​gli·​on | \ ˈgaŋ-glē-ən \
plural ganglia\ ˈgaŋ-​glē-​ə \ also ganglions

Definition of ganglion

1 : a small cystic tumor connected either with a joint membrane or tendon sheath
2a : 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

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Other Words from ganglion

ganglionated \ ˈgaŋ-​glē-​ə-​ˌnā-​təd \ adjective
ganglionic \ ˌgaŋ-​glē-​ˈä-​nik \ adjective

Examples of ganglion in a Sentence

Recent Examples on the Web

Migraines, this theory holds, start when the spreading electrical wave activates the trigeminal ganglion, a cluster of neurons that sit close to the brainstem. Tony Dajer, Discover Magazine, "Vertigo, Panic and Trouble Breathing: What's Going On Here?," 19 Oct. 2018 Fewer than 5 percent of the neurons, called retinal ganglion cells, grew back. Rebecca Robbins, STAT, "A daredevil researcher’s latest quest: to restore sight lost to glaucoma using virtual reality," 2 July 2018 These wavelength-sensitive photoreceptors were identified soon after and are known as melanopsin-containing ganglion cells. Jessica Schmerler, Scientific American, "Q&A: Why Is Blue Light before Bedtime Bad for Sleep?," 1 Sep. 2015 With oral herpes, HSV-1 hangs out in the trigeminal ganglion, a nerve cluster in your skull. Becky Little, Smithsonian, "Can We Gene-Edit Herpes Away?," 23 Mar. 2018 This includes ipRGCs, or intrinsically photosensitive retinal ganglion cells. Brittany Nader,, "University of Akron biology professor, team of scientists make breakthrough discovery on vision," 17 Jan. 2018 The U.S. Army is researching an anesthetic injection​ called a stellate ganglion block ​that could relieve symptoms of post-traumatic stress disorder. Michael M. Phillips, WSJ, "Can a Single Injection Conquer PTSD? The Army Wants to Find Out," 12 June 2017 The chip electrically stimulates the retina so ganglion cells can pick up the images. Rachel Metz, WIRED, "A Question of Mind Over Matter," 20 Sep. 2006

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ganglion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of ganglion

1597, in the meaning defined at sense 1

History and Etymology for ganglion

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

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Time Traveler for ganglion

The first known use of ganglion was in 1597

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English Language Learners Definition of ganglion

medical : a mass of nerve cells


gan·​gli·​on | \ ˈgaŋ-glē-ən \
plural ganglia\ -​glē-​ə \

Kids Definition of ganglion

: a mass of nerve cells especially outside the brain or spinal cord


gan·​gli·​on | \ ˈgaŋ-glē-ən \
plural -glia\ -​glē-​ə \ also ganglions

Medical Definition of ganglion

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
2a : 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

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More from Merriam-Webster on ganglion

Rhyming Dictionary: Words that rhyme with ganglion

Spanish Central: Translation of ganglion

Nglish: Translation of ganglion for Spanish Speakers

Britannica English: Translation of ganglion for Arabic Speakers Encyclopedia article about ganglion

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