volatile

/ˈvɑlətəl/
adjective
  1. Likely to change suddenly and unexpectedly, especially for the worse.
    • Her mood is volatile; one moment she is happy, the next she is angry.
    • The stock market has been very volatile this week, with prices swinging wildly.
    • Relations between the two countries remain volatile after the border dispute.
  2. (of a substance) easily evaporating at normal temperatures.
    • Gasoline is a volatile liquid that gives off flammable vapors.
    • The perfume contains volatile oils that quickly disappear when exposed to air.
    • Volatile chemicals must be stored in sealed containers to prevent evaporation.
  3. (of a person) liable to display rapid, strong, and unpredictable changes of emotion.
    • She can be volatile when she feels stressed, so we try to stay calm around her.
    • The coach is known for his volatile temper, often shouting at players during games.
    • His volatile personality made it hard for him to keep friends for long.
noun
  1. A volatile substance, especially a chemical that evaporates quickly.
    • The lab technician handled the volatiles with care to avoid any fumes.
    • The factory stores its volatiles in a special ventilated room.
    • Many cleaning products contain volatiles that can be harmful if inhaled.