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Synonyms

spontaneously

American  
[spon-tey-nee-uhs-lee] / spɒnˈteɪ ni əs li /

adverb

  1. naturally, without premeditation, prompting, or planning.

    The author recounts how a fully-fledged exchange market economy emerged spontaneously in his POW camp.

    These answers were given spontaneously to an open-ended question that did not offer response options.

  2. in an impulsive way.

    It was so cold the other night that I spontaneously booked a trip to Turks and Caicos.

  3. by a natural process or from an internal force or cause.

    A calf should normally stand spontaneously within 60–90 minutes of its birth.

    The symptoms resolved spontaneously within 6 months of onset.


Other Word Forms

Etymology

Origin of spontaneously

spontaneous ( def. ) + -ly

Explanation

When you do something spontaneously, you do it on a whim, without preparing for it or giving it much thought. If your math teacher spontaneously breaks into a tap dance, it will surprise the whole class. Spontaneously belting out a song on the subway is very different from practicing over many weeks for a choral concert solo. Things that happen spontaneously aren't planned: improvisation in music or theater, for example, happens spontaneously. Spontaneously comes from the adjective spontaneous, with its Late Latin root spontaneus, "willing," or "of one's free will."

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Vocabulary lists containing spontaneously

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.

Spontaneously, I’d joined a group of old friends on their way to a house party in Hollywood.

From Los Angeles Times • Aug. 15, 2025

Spontaneously changing footwear isn't the worst problem he's faced, though.

From BBC • May 14, 2025

Spontaneously, “they just showed up one day,” said Melissa Russell Paige, who has lived in the same second floor Brooklyn apartment for 8 years and “never saw an ant even once.”

From New York Times • Jul. 10, 2022

Upset: Spontaneously take your husband up on his offer to view his text exchanges.

From Washington Post • Nov. 30, 2021

Spontaneously several voices cried out, “Help! Help us!”

From "The Devil's Arithmetic" by Jane Yolen

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