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.

Pope Francis was often seen as a spontaneous progressive, who sometimes alienated Catholic traditionalists - for example in his restrictions on Latin Mass, which Pope Leo has eased.

From BBC • Apr. 15, 2026

They quickly return to a lower energy state by releasing light at a specific frequency, a process known as spontaneous emission.

From Science Daily • Apr. 10, 2026

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

From Slate • Apr. 3, 2026

The archive also contains spontaneous encounters that became landmark moments over time.

From Los Angeles Times • Mar. 23, 2026

Not many institutions can produce this spontaneous music at will, summer after summer, year after year.

From "The Lives of a Cell" by Lewis Thomas

Vocabulary lists containing spontaneous

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