spontaneous
Americanadjective
-
coming or resulting from a natural impulse or tendency; without effort or premeditation; natural and unconstrained; unplanned.
a spontaneous burst of applause.
- Synonyms:
- free, unpremeditated
- Antonyms:
- premeditated
-
(of a person) given to acting upon sudden impulses.
-
(of natural phenomena) arising from internal forces or causes; independent of external agencies; self-acting.
-
growing naturally or without cultivation, as plants and fruits; indigenous.
-
produced by natural process.
adjective
-
occurring, produced, or performed through natural processes without external influence
spontaneous movement
-
arising from an unforced personal impulse; voluntary; unpremeditated
a spontaneous comment
-
(of plants) growing naturally; indigenous
Usage
What does spontaneous mean? Spontaneous means natural and unplanned. When you describe an action or event as spontaneous, it means it happened naturally, without having been planned, as in The meeting turned into a spontaneous dance party. When something that someone does is described as spontaneous, it means it was done out of a natural impulse, without having been thought about beforehandWhen spontaneous is used to describe a person, it means they have a tendency to or are known for doing things impulsively and without planning. This is usually used in a positive way to portray them as a fun person who is adventurous and willing to do things on the spur of the moment. Telling someone to be more spontaneous means you want them to be more flexible and willing to do more things on a whim instead of needings for things to be completely structured or scheduled. The state or quality of being spontaneous is spontaneity. In a scientific context, spontaneous is used to describe effects that happen independently, without being acted on by outside forces. The most well-known example of its use in this sense is in the term spontaneous combustion, in which something catches on fire due to an internal chemical reaction (as opposed to external ignition). Example: Julian’s friends knew him as a spontaneous guy who was always up for going on random adventures.
Synonym Usage
Other Word Forms
Etymology
Origin of spontaneous
First recorded in 1650–60; from Late Latin spontāneus, equivalent to Latin spont(e) “willingly” + -āneus ( -ān(us) -an + -eus -eous )
Explanation
Something spontaneous happens when you're least expecting it. Spontaneous things are natural or instinctive, and they happen without warning. If you plan to go to a movie and then you go, that's not a spontaneous thing. Ditching the movie at the last minute to go to the park? That's spontaneous. Spontaneous things happen all of a sudden, on the spur of the moment, without being planned. Spontaneous can also refer to things that happen without outside influence. Your parents will be happy if you do your chores spontaneously instead of waiting till they nag you.
Vocabulary lists containing spontaneous
Essential Academic Vocabulary for High School Students, List 1
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100 Top "SAT" Words
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Animal Farm
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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.
But some users find that much like the models they’re built on—which can hallucinate, misinterpret or even commit spontaneous acts of cybercrime—their assistants, too, can behave unpredictably.
From The Wall Street Journal ● Oct. 8, 2026
The force said they were detained when a "spontaneous protest" was staged outside the Camden headquarters of the UK's largest Jewish community group.
From BBC ● Oct. 7, 2026
But the tale of that Thursday’s spontaneous, viral resistance is narrated by its proud participants.
From Los Angeles Times ● Oct. 2, 2026
I’ve noticed how much more spontaneous social interactions are here.
From Salon ● Sep. 30, 2026
It was a good bandage, he knew, and he sat back on his heels with pride, wiping the perspiration from his brow, and grinned at Snowden with spontaneous friendliness.
From "Catch-22" by Joseph Heller
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
