involuntary

adjective

in·​vol·​un·​tary (ˌ)in-ˈvä-lən-ˌter-ē 

-ˌte-rē

1

: done contrary to or without choice

2

: compulsory

3

: not subject to control of the will : reflex

involuntarily

(ˌ)in-ˌvä-lən-ˈter-ə-lē 

-ˈte-rə-

adverb

involuntariness

(ˌ)in-ˈvä-lən-ˌter-ē-nəs 

-ˌte-rē-

noun

Synonyms

• coerced
• forced
• unintended
• unintentional
• unwilling
• will-less

Examples of involuntary in a Sentence

Breathing and circulation are involuntary processes.

When the door burst open, she let out an involuntary shriek.

The lawyer argued that the client's confession was involuntary.

Recent Examples on the Web

Threaten the rubber hand by attempting to stab it with a dagger, for instance, and the participants exhibit an involuntary startle or fear response. —ArsTechnica, 31 Mar. 2025

On Thursday, the Cook County state’s attorney’s office approved felony charges of one count each of promoting prostitution, trafficking for labor/recruits, trafficking for labor/benefits and involuntary solitude causing financial harm. —Adriana Pérez, Chicago Tribune, 30 Mar. 2025

What Is Chorea? Chorea is a characteristic type of involuntary movement in Huntington’s disease. —Heidi Moawad, Verywell Health, 27 Mar. 2025

Office leases are being terminated across multiple states, and some reassignments may be involuntary, requiring retraining. —Daniel R. Depetris, Newsweek, 25 Mar. 2025

Word History

Etymology

Middle English involuntari, from Late Latin involuntarius, from Latin in- + voluntarius voluntary

First Known Use

15th century, in the meaning defined at sense 1

Phrases Containing involuntary

• involuntary manslaughter
• involuntary muscle

Rhymes for involuntary

• accretionary
• apothecary
• bicentenary
• certiorari
• concessionary
• concretionary
• confectionary
• confectionery
• constabulary
• contemporary
• deflationary
• depositary

Kids Definition

involuntary

adjective

in·​vol·​un·​tary (ˈ)in-ˈväl-ən-ˌter-ē 

1

: not made or done willingly or from choice : unwilling

2

: being enforced or required : mandatory

3

: not normally under the control of the will

an involuntary response to a stimulus

involuntarily

(ˌ)in-ˌväl-ən-ˈter-ə-lē 

adverb

Medical Definition

involuntary

adjective

in·​vol·​un·​tary (ˈ)in-ˈväl-ən-ˌter-ē 

: not subject to control of the will : reflex

involuntary contractions

Legal Definition

involuntary

adjective

in·​vol·​un·​tary in-ˈvä-lən-ˌter-ē 

: done, made, or initiated contrary to or without one's choice

an involuntary confession

an involuntary lien

an involuntary plaintiff joined in the action

involuntarily adverb