ENGLISH
REFERENCE

spontaneous

adj.
US //spɑnˈteɪniəs// UK //spɒntˈeɪniəs// spon·ta·neous
  1. 1 unplanned or impulsive (adj.)
    B2 Upper Intermediate

    done or said in a natural way without being planned first.

    arising from a momentary impulse or natural feeling rather than premeditation.

    Example

    We made a spontaneous decision to go to the beach since the weather was so beautiful.

    Example

    The crowd broke into spontaneous applause as the soloist finished her performance, a reaction that clearly moved the young musician.
  2. 2 happening naturally (adj.)
    C1 Advanced Technical Science

    happening on its own without any outside cause or help.

    occurring without apparent external influence or cause; self-generated.

    Example

    The forest fire was caused by spontaneous combustion in the dry heat.

    Example

    The chemical reaction was entirely spontaneous, requiring no external heat source to initiate the transformation of the compounds.
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  1. 3 wild or uncultivated (adj.)
    C2 Proficiency Literary

    growing or produced naturally without people planting or managing it.

    produced without human cultivation, labour, or intentional planting.

    Example

    The garden was filled with the spontaneous growth of local wildflowers.

    Example

    The valley was noted for its spontaneous vegetation, where rare orchids flourished without any human intervention for centuries.
Origin

Learned borrowing from Late Latin spontāneus.

Word family

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