spontaneous

[spon-tey-nee-uhs] / spɒnˈteɪ ni əs /

ADJECTIVE

impulsive, willing

Synonyms

STRONGEST

casual impromptu instinctive offhand simple unplanned voluntary

WEAK

ad-lib automatic break loose down extemporaneous extempore free free-spirited from the hip impetuous improvised inevitable involuntary irresistible natural off top of head off-the-cuff unartful unavoidable unbidden uncompelled unconscious unconstrained uncontrived uncontrolled unforced unintentional unpremediated unprompted unsophisticated unstudied up front

Antonyms

STRONGEST

deliberate planned

WEAK

intended premeditated

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.

"We got a return of spontaneous circulation," Page said.

From BBC • Apr. 6, 2026

This one-sided empathy is not a spontaneous response to compelling facts, however.

From Slate • Apr. 3, 2026

This type of spontaneous movement has been linked to longevity in other species as well.

From Science Daily • Mar. 26, 2026

That kind of flexibility leads to spontaneous nights where what started off as an intimate hang expands into an all-out party.

From Los Angeles Times • Mar. 26, 2026

I started dating a football player who was smart and spontaneous, who liked to have fun.

From "Becoming" by Michelle Obama

Vocabulary lists containing spontaneous

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Animal Farm

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