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adjective spon·ta·ne·ous \spän-ˈtā-nē-əs\

Simple Definition of spontaneous

  • : done or said in a natural and often sudden way and without a lot of thought or planning

  • : doing things that have not been planned but that seem enjoyable and worth doing at a particular time

Source: Merriam-Webster's Learner's Dictionary

Full Definition of spontaneous

  1. 1 :  proceeding from natural feeling or native tendency without external constraint

  2. 2 :  arising from a momentary impulse

  3. 3 :  controlled and directed internally :  self-acting <spontaneous movement characteristic of living things>

  4. 4 :  produced without being planted or without human labor :  indigenous

  5. 5 :  developing or occurring without apparent external influence, force, cause, or treatment

  6. 6 :  not apparently contrived or manipulated :  natural





Examples of spontaneous in a sentence

  1. Shane has a lovely habit of paying us spontaneous visits: one time she brought over a jar of a pickle she'd recently put up; another time just a good story or two. —James Oseland, Saveur, December 2006

  2. Cold viruses can damage the olfactory system directly. This loss of smell may last even after the cold is over. Sometimes the sense comes back as suddenly as it disappeared, perhaps because even as adults we generate new olfactory neurons. Spontaneous improvement might be a person's best hope, because there are no real proven treatments for reversing olfactory nerve damage. —Harvard Health Letter, September 2001

  3. Peter Jakobsen of the European Space Agency, which built the Faint Object Camera, drew spontaneous applause at the January meeting when he showed an image of supernova SN1987A from the instrument. —Kristin Leutwyler, Scientific American, March 1994

  4. The comment was completely spontaneous.

  5. He's a guy who's spontaneous and fun.

Did You Know?

Spontaneous derives, via the Late Latin spontaneus, from the Latin sponte, meaning "of one's free will, voluntarily," and first appeared in English in the mid-17th century. Thomas Hobbes was an early adopter: he wrote that "all voluntary actions … are called also spontaneous, and said to be done by man's own accord" in his famous 1656 The Questions Concerning Liberty, Necessity, and Chance. Today the word is more often applied to things done or said in a natural and often sudden way, without a lot of thought or planning—or to people who do or say things in such a way.

Origin and Etymology of spontaneous

Late Latin spontaneus, from Latin sponte of one's free will, voluntarily

First Known Use: 1653

Synonym Discussion of spontaneous

spontaneous, impulsive, instinctive, automatic, mechanical mean acting or activated without deliberation. spontaneous implies lack of prompting and connotes naturalness <a spontaneous burst of applause>. impulsive implies acting under stress of emotion or spirit of the moment <impulsive acts of violence>. instinctive stresses action involving neither judgment nor will <blinking is an instinctive reaction>. automatic implies action engaging neither the mind nor the emotions and connotes a predictable response <his denial was automatic>. mechanical stresses the lifeless, often perfunctory character of the response <a mechanical teaching method>.

SPONTANEOUS Defined for Kids


adjective spon·ta·ne·ous \spän-ˈtā-nē-əs\

Definition of spontaneous for Students

  1. 1 :  done, said, or produced freely and naturally <spontaneous laughter>

  2. 2 :  acting or taking place without outside force or cause <a spontaneous fire>



Medical Dictionary


adjective spon·ta·ne·ous \spän-ˈtā-nē-əs\

Medical Definition of spontaneous

  1. 1:  proceeding from natural feeling or native tendency without external constraint

  2. 2:  developing without apparent external influence, force, cause, or treatment <a spontaneous nosebleed>



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a dwelling place or home

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