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Showing results for spontaneous.
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

Vance, though, is clearly incapable of such a spontaneous response.

From Salon • Apr. 1, 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

Their analysis revealed that slightly more than 10% of cell divisions produce spontaneous chromosomal abnormalities.

From Science Daily • Mar. 10, 2026

I thought of theory number five: spontaneous combustion.

From "The London Eye Mystery" by Siobhan Dowd

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.