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

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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

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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.

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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

Explanation

Involuntary describes a reflex or action done without conscious control or will — like a blink, a sneeze, a yawn, or “the giggles.” If you volunteered to do it, it’s voluntary. If you didn’t volunteer, but you find yourself doing it anyway, it’s involuntary. This can go for the involuntary hiccups you wrestle with on your blind date, as well as the involuntary task you do at your manager’s insistence. Involuntary gets a lot of blame, but something that is involuntary is not necessarily bad: Breathing is involuntary, but you would probably do it anyway if given the choice.

Example Sentences

"Involuntary installations have been a last – but necessary – resort for cases where repeated attempts to address debt with the customer through other means have been unsuccessful," she said.

From BBC • May 27, 2025

Involuntary servitude, however, is still in the Constitution.

From Los Angeles Times • Nov. 17, 2024

Officers detained Iosefo under the Involuntary Treatment Act and took him to a hospital, the charges say.

From Seattle Times • May 26, 2024

Involuntary psychiatric detentions among youth, however, are at an all-time high in the province.

From Salon • May 27, 2023

It possesses also its own specialised system of muscles, the "Involuntary muscles"; which are not under control of the conscious brain and will, but operate automatically—by so-called reflex action.

From Feminism and Sex-Extinction by Kenealy, Arabella

Related Words

• compulsory
• forced
• spontaneous
• uncontrolled
• unintentional