neuron

noun

neu·​ron ˈnü-ˌrän  ˈnyü-  ˈnu̇r-ˌän 

ˈnyu̇r-

: a grayish or reddish granular cell that is the fundamental functional unit of nervous tissue transmitting and receiving nerve impulses and having cytoplasmic processes which are highly differentiated frequently as multiple dendrites or usually as solitary axons which conduct impulses to and away from the cell body : nerve cell sense 1

neuronal

ˈnu̇r-ə-nᵊl 

ˈnyu̇r-;

  nu̇-ˈrō-nᵊl 

nyu̇-

adjective

or less commonly neuronic

nu̇-ˈrä-nik 

nyu̇-

Illustration of neuron

• 1 cell body
• 2 dendrite
• 3 axon
• 4 nerve ending

Examples of neuron in a Sentence

Recent Examples on the Web

Tunneling neurons While most human organs undergo frequent cellular updates, our brains are largely restricted to the neurons present at birth. —Mrigakshi Dixit, Interesting Engineering, 17 Apr. 2026

Aging and damaged brain cells, or neurons, can cause memory problems and limit the brain’s ability to recover from illnesses. —K. R. Callaway, Scientific American, 17 Apr. 2026

But technologies like functional MRI can't show what individual neurons are doing. —Jon Hamilton, NPR, 14 Apr. 2026

The neurons in the substantia nigra produce dopamine, which is a neurotransmitter that plays a vital role in controlling movement. —Mason Leib, ABC News, 13 Apr. 2026

Word History

Etymology

borrowed from German Neuron, borrowed from Greek neûron "sinew, tendon, nerve" — more at nerve entry 1

Note: Term introduced by the German anatomist Heinrich Wilhelm Waldeyer (Heinrich Wilhelm Gottfried von Waldeyer-Hartz, 1836-1921) in "Ueber einige neuere Forschungen im Gebiete der Anatomie der Centralnervensystems," Berliner klinische Wochenschrift, 28. Jahrgang, no. 28, July 13, 1891, p. 691: "Somit besteht ein Nervenelement (eine 'Nerveneinheit' oder 'Neuron', wie ich es zu nennen vorschlagen möchte), den genannten Forschungsergebnissen … zufolge, aus nachstehenden Stücken: a) einer Nervenzelle, b) dem Nervenfortsatze, c) dessen Collateralen und d) dem Endbäumchen." — "Therefore, in accordance with the cited research results, a nerve element (a 'nerve unit' or 'neuron,' as I would like to suggest as a name), consists of the following parts: a) a nerve cell, b) the nerve process [= axon], c) its collaterals and d) the end tree [= axon terminals]." Waldeyer apparently intended -on to be taken as a suffix, indicating a unit, rather than the Greek neuter singular inflectional ending, as he utilized Neuronen as the plural in the same article. Cf. French neurone and the English variant neurone.

First Known Use

1891, in the meaning defined above

Phrases Containing neuron

• associative neuron
• motor neuron

Rhymes for neuron

• motoneuron

Kids Definition

neuron

noun

neu·​ron ˈn(y)ü-ˌrän  ˈn(y)u̇(ə)r- ˌän 

: a grayish or reddish cell that is the basic working unit of the nervous system and has an axon and dendrites that carry nerve impulses

Medical Definition

neuron

noun

neu·​ron ˈn(y)ü-ˌrän  ˈn(y)u̇(ə)r-ˌän 

variants also neurone

-ˌrōn, -ˌōn 

: one of the cells that constitute nervous tissue, that have the property of transmitting and receiving nerve impulses, and that are composed of somewhat reddish or grayish protoplasm with a large nucleus containing a conspicuous nucleolus, irregular cytoplasmic granules, and cytoplasmic processes which are highly differentiated frequently as multiple dendrites or usually as solitary axons and which conduct impulses toward and away from the cell body : nerve cell sense 1

neuronal

ˈn(y)u̇r-ən-ᵊl  n(y)u̇-ˈrōn-ᵊl 

adjective

also neuronic

n(y)u̇-ˈrän-ik