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Synonyms

involuntary

American  
[in-vol-uhn-ter-ee] / ɪnˈvɒl ənˌtɛr i /

adjective

  1. not voluntary; independent of one's will; not by one's own choice.

    an involuntary listener; involuntary servitude.

  2. unintentional; unconscious.

    an involuntary gesture.
    Synonyms:
    instinctive
    Antonyms:
    intentional

  3. Physiology. acting independently of or done or occurring without volition.

    involuntary muscles.
    Synonyms:
    uncontrolled, reflex
involuntary British  
/ -trɪ, ɪnˈvɒləntərɪ /

adjective

  1. carried out without one's conscious wishes; not voluntary; unintentional

  2. physiol (esp of a movement or muscle) performed or acting without conscious control

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
involuntary Scientific  
/ ĭn-vŏl′ən-tĕr′ē /

  1. Not under conscious control. Most of the biological processes in animals that are vital to life, such as contraction of the heart, blood flow, breathing, and digestion, are involuntary and controlled by the autonomic nervous system.

Related Words

See automatic.

Other Word Forms

  • involuntarily adverb
  • involuntariness noun

Etymology

Origin of involuntary

From the Late Latin word involuntārius, dating back to 1525–35. See in- 3, voluntary

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

A last resort would be a conservatorship, which is an involuntary process and takes place when a person is unable to take care of their finances.

From MarketWatch • Mar. 23, 2026

Critics of involuntary civil-commitment programs argue they violate civil liberties and stigmatize mental illness.

From The Wall Street Journal • Mar. 11, 2026

“The panel noted that the laws regarding a seaman’s manslaughter differ from those of involuntary manslaughter.”

From Los Angeles Times • Mar. 3, 2026

A regional court in Katowice sentenced one, who was also charged with causing involuntary manslaughter, to 18 months in prison and barred him from practicing medicine for six years.

From Barron's • Mar. 3, 2026

Zipping over the rapids at twenty or thirty miles per hour, I hear an involuntary bark of fright leap from my throat before I realize that I'm in no danger and regain my composure.

From "Into the Wild" by Jon Krakauer

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.