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Showing results for spontaneous. Search instead for spontaneousne.
Definitions

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.

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

From Slate • Apr. 3, 2026

Two shows, games and spontaneous dance parties are hallmarks of the experience, as Disneyland’s live entertainment team sought to translate the show’s particular broadcast-based appeal to the real world.

From Los Angeles Times • Mar. 22, 2026

"So it started with that flame. It was like spontaneous combustion."

From BBC • Mar. 17, 2026

They want the gathering to feel casual, spontaneous — the sort of event where everyone simply appears with something charming and the table somehow assembles itself.

From Salon • Mar. 15, 2026

It was a splendid, uproarious, spontaneous celebration, with hugs and handshakes and kisses all around, and eventually Milligan produced the remains of last night’s birthday cake and Rhonda whipped up a frothy fruit punch.

From "The Mysterious Benedict Society" by Trenton Lee Stewart