Definition of spontaneousnext

Synonym Chooser

How is the word spontaneous distinct from other similar adjectives?

Some common synonyms of spontaneous are automatic, impulsive, instinctive, and mechanical. While all these words mean "acting or activated without deliberation," spontaneous implies lack of prompting and connotes naturalness.

a spontaneous burst of applause

In what contexts can automatic take the place of spontaneous?

The meanings of automatic and spontaneous largely overlap; however, automatic implies action engaging neither the mind nor the emotions and connotes a predictable response.

his denial was automatic

When is it sensible to use impulsive instead of spontaneous?

In some situations, the words impulsive and spontaneous are roughly equivalent. However, impulsive implies acting under stress of emotion or spirit of the moment.

impulsive acts of violence

When could instinctive be used to replace spontaneous?

The synonyms instinctive and spontaneous are sometimes interchangeable, but instinctive stresses action involving neither judgment nor will.

blinking is an instinctive reaction

Where would mechanical be a reasonable alternative to spontaneous?

The words mechanical and spontaneous are synonyms, but do differ in nuance. Specifically, mechanical stresses the lifeless, often perfunctory character of the response.

a mechanical teaching method

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of spontaneous This project grew out of a spontaneous scientific discussion. Georgina Jedikovska, Interesting Engineering, 23 Feb. 2026 So spontaneous ignition can happen too early or too late in the stroke under HCCI. New Atlas, 23 Feb. 2026 The Ocoee Massacre was not a spontaneous outburst of violence. Debbie Deland, The Orlando Sentinel, 22 Feb. 2026 If no underlying cause is found, the patient may have chronic spontaneous urticaria. Zia Sherrell, Health, 20 Feb. 2026 See All Example Sentences for spontaneous
Recent Examples of Synonyms for spontaneous
Adjective
  • Still, the majority negative opinions about the president don't appear to translate into an automatic boon for Democrats.
    Kathryn Palmer, USA Today, 22 Feb. 2026
  • While riding mowers include safety functions such as automatic shut-offs, blade brakes, and rollover protection, the sheer size of the machine increases the injury risk if it is not properly handled.
    Nadia Hassani, The Spruce, 22 Feb. 2026
Adjective
  • The researchers found that the cells retained mechanical integrity under bending, stretching, and compression.
    Bojan Stojkovski, Interesting Engineering, 21 Feb. 2026
  • For instance, multilayer plastic bags — those that hold snack chips, candy and coffee beans — are the scourge of municipal garbage haulers because they cannot be recycled, and if put in the blue bins, can damage mechanical sorting machines.
    Los Angeles Times, Los Angeles Times, 21 Feb. 2026
Adjective
  • Earthquakes' sudden, rapid shaking can cause fires, tsunamis, landslides or avalanches.
    CA Earthquake Bot, Sacbee.com, 26 Feb. 2026
  • Porzingis — who the Warriors traded Jonathan Kuminga and Buddy Hield for — had also missed Sunday’s win over the Nuggets with a sudden illness.
    Joseph Dycus, Mercury News, 25 Feb. 2026
Adjective
  • There was a reflex stop on a David Kämpf flash rebound in the second period.
    Mark Lazerus, New York Times, 18 Feb. 2026
  • After your baby is born progesterone (which inhibits breastmilk production) drops and prolactin, which controls milk volume, and oxytocin, which triggers the let-down reflex increases, explains Nadine Rosenblum, the perinatal lactation program coordinator at The Johns Hopkins Hospital.
    Hannah Silverman, Parents, 16 Feb. 2026
Adjective
  • Lunar rocks and soil offered novel insights into the moon’s origin and composition, and more recent analysis of previously untouched Apollo samples, as well as samples retrieved by robotic missions, revealed the surprising discovery of water trapped in rocks thought to be bone-dry.
    Ashley Strickland, CNN Money, 21 Feb. 2026
  • The Paiza Collection’s 160 butlers go through an extensive training program, and what that produces isn’t just robotic precision but also a culture of genuinely warm hospitality.
    Condé Nast, Condé Nast Traveler, 21 Feb. 2026
Adjective
  • Allen is productive and instinctive.
    Joseph Hoyt, Dallas Morning News, 24 Feb. 2026
  • The instinctive Moon slips into your 6th House of Work, nudging you to adjust routines so your energy stretches further.
    Tarot.com, Chicago Tribune, 21 Feb. 2026
Adjective
  • Rosalba worked in the accounting department of a mail order catalog company and later helped her husband run a mechanic shop in Granada Hills.
    Matthew Ormseth, Los Angeles Times, 19 Feb. 2026
  • Approximately 55 bus driver, bus monitor and mechanic roles will be cut.
    Kathryn Muchnick, Louisville Courier Journal, 13 Feb. 2026
Adjective
  • Olive oil is also used to dress simple salads, roasted vegetables, and a host of other dishes.
    Condé Nast Traveler, Condé Nast Traveler, 26 Feb. 2026
  • Others have argued that the game represents a simple life that is becoming harder to obtain.
    Jacqui Palumbo, CNN Money, 26 Feb. 2026

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Cite this Entry

“Spontaneous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/spontaneous. Accessed 27 Feb. 2026.

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