: 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

Illustration of neuron

Illustration of neuron
  • 1 cell body
  • 2 dendrite
  • 3 axon
  • 4 nerve ending

Examples of neuron in a Sentence

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Pattern Generation As new findings accrued, Picard came to see brain function as shaped not only by molecules, neurons, and circuits, but also by how energy is transformed and patterned. Rachel Nuwer, Quanta Magazine, 17 July 2026 Where Prozac and similar drugs slowly change the chemicals in the brain, psychedelics may quickly prompt neurons to create new connections. Angelica Peebles, CNBC, 16 July 2026 Those plaques accumulate in the brain over the course of decades and cause neurons to die, which can result in dementia. Charna Flam, PEOPLE, 16 July 2026 The amyloid plaques, which trigger inflammation and damage communication between neurons, can collect in the brain decades before memory loss or cognitive decline — even when people are in their 30s and 40s. Sandee Lamotte, CNN Money, 15 July 2026 See All Example Sentences for neuron

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

Time Traveler
The first known use of neuron was in 1891

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Cite this Entry

“Neuron.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/neuron. Accessed 24 Jul. 2026.

Kids Definition

: 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

: 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

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