motor neuron


Definition of motor neuron

: a neuron that passes from the central nervous system or a ganglion toward a muscle and conducts an impulse that causes movement

called also motoneuron

Examples of motor neuron in a Sentence

Recent Examples on the Web The drug, injected directly into the cerebrospinal fluid, binds to the RNA for a second motor neuron gene that, like the gene targeted by Zolgensma, encodes the protein missing in the condition. Lydia Denworth, Science | AAAS, "Is gene therapy ready to treat some forms of autism?," 14 Oct. 2020 Now researchers believe the problem is not actually with the muscle itself, but with the motor neurons that send signals to it, which become hyperactive. Cara Rosenbloom,, "What science has to say about these age-old health adages," 18 Oct. 2019 Zolgensma delivers a healthy copy of the human SMN gene to a patient’s motor neurons in a single treatment. Jim Daley, Scientific American, "Gene Therapy Arrives," 24 Dec. 2019 Unable to pinpoint a cause, researchers have focused on understanding the process that kills the motor neurons., "FDA-approved drugs can slow its progression or treat some of its symptoms, but so far there is no treatment that stops ALS.," 12 Dec. 2019 The dearth of the protein debilitates motor neurons, which are responsible for relaying messages to muscles, and creates a cascade of issues that culminates in muscle weakness. Andrew Joseph, STAT, "A lottery like no other offers up a cutting-edge medicine — with lives on the line," 7 Feb. 2020 The 27-year-old author and speaker—who, alongside his fiancée, Hannah Aylward, is one half of the YouTube duo Squirmy and Grubs—has spinal muscular atrophy, a genetic disorder that affects motor neurons and causes muscle wasting and weakness. Michael Schulson, Quartz, "The flawed logic that makes flying a nightmare for wheelchair users," 6 Dec. 2019 Some of these genes are also linked to the motor neuron degenerative disease ALS (amyotrophic lateral sclerosis), which is why the two often co-occur, per the NINDS. Carolyn L. Todd, SELF, "8 Things to Know About Frontotemperal Degeneration," 25 Oct. 2019

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

See More

First Known Use of motor neuron

1898, in the meaning defined above

Keep scrolling for more

Learn More about motor neuron

Time Traveler for motor neuron

Time Traveler

The first known use of motor neuron was in 1898

See more words from the same year

Statistics for motor neuron

Last Updated

23 Oct 2020

Cite this Entry

“Motor neuron.” Dictionary, Merriam-Webster, Accessed 26 Oct. 2020.

Keep scrolling for more

More Definitions for motor neuron

motor neuron


Medical Definition of motor neuron

: a neuron that passes from the central nervous system or a ganglion toward or to a muscle and conducts a nerve impulse that causes movement

called also motoneuron

— compare interneuron, sensory neuron

More from Merriam-Webster on motor neuron Encyclopedia article about motor neuron

Comments on motor neuron

What made you want to look up motor neuron? Please tell us where you read or heard it (including the quote, if possible).


Test Your Vocabulary

Namesakes Word Quiz

  • a citrus fruit possibly named after a person
  • Which of the following is a fruit named after a Moroccan seaport?
Spell It

Can you spell these 10 commonly misspelled words?


Test Your Knowledge - and learn some interesting things along the way.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!