English Reference
Adverb

spontaneously

adv. manner
B2 Upper Intermediate US /spɑnˈteɪniəsɫi/ UK /spɒntˈeɪniəsli/ spon·ta·neous·ly

adv.to do something suddenly because you want to, without planning it first. It describes an action that happens naturally on its own.

adv.occurring as a result of a sudden inner impulse or inclination and without premeditation. Often describes natural processes that occur without external influence.


SIMPLE

The crowd spontaneously started to cheer.

CONTEXTUAL

After the performance ended, the audience spontaneously rose for a standing ovation despite no one leading the applause.

COMPLEX

In certain chemical environments, the compound may spontaneously ignite when exposed to oxygen, requiring researchers to handle the substance within a strictly controlled vacuum.

Usage

Typically placed before the main verb or at the end of a clause to describe how an action occurs.

Pitfall
He did it spontaneousHe did it spontaneously

Learners often use the adjective form 'spontaneous' when the adverbial form is required to modify a verb.

A growing 53% of consumers spontaneously mentioned that high prices are weighing down current personal finances, up from 50% last month and 45% in January 2026.

Phys.org· 28 Aug 2026

After receiving prosthe6, however, the blind mice once again spontaneously favored dark areas.

ScienceDaily· 28 Aug 2026

From spontaneous + -ly.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Level B2 · Upper Intermediate
Frequency Frequent
Updated