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
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
100 Top "SAT" Words
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
Animal Farm
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
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.
Base told Rolling Stone in a 2014 interview the song's creation was spontaneous and he was shocked by its success.
From BBC • May 23, 2026
Most cancers are spontaneous and can’t be detected in a genetic test.
From Barron's • May 21, 2026
“She had a spontaneous unexplained brain bleed that led to brain death.”
From Salon • May 7, 2026
And what better indication of the demise of the spontaneous phone call can be found?
From The Wall Street Journal • May 1, 2026
Citra knew it would be healed by morning, but the healing nanites were not spontaneous.
From "Scythe" by Neal Shusterman
![]()
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.