Synonyms for volatile

modified

1. Having the qualities of a gas

   light, airy, imponderable, subtle, buoyant, gaseous, gasiform, vaporous, vapory, vaporizable, evaporable, effervescent, expansive, resilient, elastic.

   Antonyms heavy*, dense, solid.

2. Having a sprightly temperament

   lively, light-hearted, vivacious, gay, animated, merry, flippant, teasing, playful, sprightly; see also active 1, 2, happy 1.

   Antonyms solemn*, demure, quiet.

3. Liable to sudden change

   unstable, unpredictable, explosive; see changeable 1, 2.

4. Fickle

   frivolous, capricious, whimsical; see changeable 1, fickle 2.