involuntary muscle

noun

: muscle governing reflex functions and not under direct voluntary control
especially : smooth muscle

Examples of involuntary muscle in a Sentence

Recent Examples on the Web Focal dystonia, a neurological disorder that causes involuntary muscle spasms, may also cause the twisties. Colleen Murphy, Health, 22 Mar. 2024 According to the National Institutes of Health, dystonia is a neurological movement disorder seen in MS that's characterized by involuntary muscle contractions that cause slow repetitive movements or abnormal postures that can sometimes be painful. Vanessa Etienne, Peoplemag, 27 Nov. 2023 As the creature’s 14-foot-long body was convulsed by one last set of involuntary muscle contractions, its powerful sharklike tail twitched and stirred the bottom mud. Robert Baker, Discover Magazine, 12 Nov. 2019 For example, a person is not to be blamed for striking someone if that behavior resulted from an involuntary muscle spasm in the arm. James Ryerson, BostonGlobe.com, 18 July 2023 There are already more than 100,000 people around the world using deep brain stimulation to ease the involuntary muscle movements associated with Parkinson’s disease. Carl Engelking, Discover Magazine, 27 May 2014 Movement disorders were also symptoms of a post-COVID brain, including tremors, involuntary muscle contractions, epileptic seizures, hearing and vision abnormalities, and balance and coordination difficulties. Vanessa Etienne, Peoplemag, 23 Sep. 2022 The first and mildest stage is heat cramps, which are characterized by involuntary muscle spasms. Joanna Thompson, Scientific American, 11 Aug. 2022 Tremors—involuntary muscle contractions—were found to show up as many as 10 years before a Parkinson's diagnosis, becoming more frequent in the two years leading up to one. Jocelyn Solis-Moreira, Health.com, 1 Apr. 2022

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'involuntary muscle.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1840, in the meaning defined above

Time Traveler
The first known use of involuntary muscle was in 1840

Dictionary Entries Near involuntary muscle

Cite this Entry

“Involuntary muscle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/involuntary%20muscle. Accessed 18 Apr. 2024.

Kids Definition

involuntary muscle

noun

Medical Definition

involuntary muscle

noun
: muscle governing reflex functions and not under direct voluntary control
especially : smooth muscle

More from Merriam-Webster on involuntary muscle

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