# spontaneous

Pronunciation: US say "spahn-TAY-nee-uhs" /spɑnˈteɪ.ni.əs/; UK say "spon-TAY-nee-uhs" /spɒnˈteɪ.ni.əs/

## Adjective

1. Done of one's own free choice or without planning; also, arising from a sudden, passing impulse.
   - Simple: Done because you chose to, or done suddenly without planning it first.
   - _Their trip to the coast was spontaneous: they packed the car an hour after the idea came up._
   - _No one had asked him to volunteer, so his offer to stay late was entirely spontaneous._
2. Coming from natural feeling or an inborn tendency, without being held in check by outside forces or by conscious control.
   - Simple: Coming naturally from your feelings, without being forced or held back.
   - _Children show a spontaneous curiosity about anything that moves._
   - _His spontaneous warmth toward strangers was something no one could fake._
3. Produced from within rather than by something outside; happening without any apparent external cause.
   - Simple: Happening by itself, with no clear cause from outside.
   - _Doctors found no injury that could account for the patient's spontaneous bleeding._
   - _Investigators ruled the barn fire spontaneous, since the damp hay had heated up and ignited on its own._
4. Said or done without being planned in advance or written out beforehand.
   - Simple: Said or done without planning it or writing it down first.
   - _Her lawyer winced when she made a spontaneous remark that was nowhere in her prepared statement._
   - _The study compared read-aloud passages with spontaneous conversation recorded in people's homes._
5. Controlled and directed from within rather than from outside; self-acting, as is the independent movement typical of living things.
   - Simple: Moving or acting by itself, controlled from inside, the way living things do.
   - _The biologists separated the animal's spontaneous movements from those triggered by touch or light._
   - _The heart muscle cells kept up their spontaneous beating even after being removed from the body._
6. Growing of its own accord rather than being planted, tended, or raised by human labor, as wild fruit and self-sown plants do.
   - Simple: Growing on its own, without being planted or cared for by people.
   - _Within a few years, spontaneous vegetation had covered the abandoned rail yard._
   - _The ecologists counted every spontaneous plant that had sprung up between the paving stones._

## Other meanings

- (adjective) Sudden, without warning.

## Origin

A learned borrowing from the Late Latin word spontāneus.

Source: DictionaryAI, https://dictionaryai.com/define/spontaneous (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).