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.
Related Words
Other Word Forms
- nonspontaneous adjective
- nonspontaneousness noun
- semispontaneous adjective
- semispontaneousness noun
- spontaneously adverb
- spontaneousness noun
- subspontaneous adjective
- subspontaneousness noun
- unspontaneous adjective
- unspontaneousness noun
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 )
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
The men were accused of working for the U.S. and Israel, though the protests around the country were spontaneous, widespread and came before the current conflict began.
From The Wall Street Journal • Mar. 19, 2026
Their analysis revealed that slightly more than 10% of cell divisions produce spontaneous chromosomal abnormalities.
From Science Daily • Mar. 10, 2026
It was the kind of spontaneous game that developed in classes without premeditation, everyone falling into a sudden conspiracy.
From "The Chocolate War" by Robert Cormier
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.
