[ spon-tey-nee-uhs ]
See synonyms for: spontaneousspontaneously on Thesaurus.com

  1. coming or resulting from a natural impulse or tendency; without effort or premeditation; natural and unconstrained; unplanned: a spontaneous burst of applause.

  2. (of a person) given to acting upon sudden impulses.

  1. (of natural phenomena) arising from internal forces or causes; independent of external agencies; self-acting.

  2. growing naturally or without cultivation, as plants and fruits; indigenous.

  3. produced by natural process.

Origin of spontaneous

First recorded in 1650–60; from Late Latin spontāneus, equivalent to Latin spont(e) “willingly” + -āneus (-ān(us) -an + -eus -eous)

synonym study For spontaneous

Other words for spontaneous

Opposites for spontaneous

Other words from spontaneous

  • spon·ta·ne·ous·ly, adverb
  • spon·ta·ne·ous·ness, noun
  • non·spon·ta·ne·ous, adjective
  • non·spon·ta·ne·ous·ness, noun
  • sem·i·spon·ta·ne·ous, adjective
  • sem·i·spon·ta·ne·ous·ness, noun
  • sub·spon·ta·ne·ous, adjective
  • sub·spon·ta·ne·ous·ness, noun
  • un·spon·ta·ne·ous, adjective
  • un·spon·ta·ne·ous·ness, noun

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use spontaneous in a sentence

  • Something of this spontaneousness and finality belonged to the character of Bret Harte.

    The Life of Bret Harte | Henry Childs Merwin
  • She was full of these graceful flatteries, that proved the more effective because of their seeming spontaneousness.

  • Another argument for the spontaneousness of growth is universal experience.

  • It would take away all spontaneousness from my conversation.

    Dodo Wonders | E. F. Benson
  • There is a spontaneousness about them we search for in vain in his work in oil and pastel.

    Millet  | Percy Moore Turner

British Dictionary definitions for spontaneous


/ (spɒnˈteɪnɪəs) /

  1. occurring, produced, or performed through natural processes without external influence: spontaneous movement

  2. arising from an unforced personal impulse; voluntary; unpremeditated: a spontaneous comment

  1. (of plants) growing naturally; indigenous

Origin of spontaneous

C17: from Late Latin spontāneus, from Latin sponte voluntarily

Derived forms of spontaneous

  • spontaneously, adverb
  • spontaneousness, noun

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012