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adjective vol·a·tile \ˈvä-lə-təl, especially British -ˌtī(-ə)l\

Simple Definition of volatile

  • : likely to change in a very sudden or extreme way

  • : having or showing extreme or sudden changes of emotion

  • : likely to become dangerous or out of control

Source: Merriam-Webster's Learner's Dictionary

Full Definition of volatile

  1. 1 :  readily vaporizable at a relatively low temperature

  2. 2 :  flying or having the power to fly

  3. 3 a :  lighthearted, lively b :  easily aroused <volatile suspicions> c :  tending to erupt into violence :  explosive <a volatile temper>

  4. 4 a :  unable to hold the attention fixed because of an inherent lightness or fickleness of disposition b :  characterized by or subject to rapid or unexpected change <a volatile market>

  5. 5 :  difficult to capture or hold permanently :  evanescent, transitory

volatileness noun
volatility play \ˌvä-lə-ˈti-lə-tē\ noun

Examples of volatile in a sentence

  1. I am beginning to hear investors say that the best way to beat this volatile market is by trading—anxiously moving in and out of securities as the market ebbs and flows. In my view there is no surer path to the poorhouse. —John W. Rogers, Jr., Forbes, 25 May 2009

  2. Usually, only a few of the volatile chemicals in a fragrance are obviously noticeable to human noses. —Ivan Amato, Science News, 24 Sept. 2005

  3. VOCs (or volatile organic compounds) are thought to be among the potential culprits behind illnesses often lumped under the heading of Sick Building Syndrome. —Scott Schilling, This Old House, March 2005

  4. … it was Elvis who represented rock and roll at its unblushing, volatile best; he was its first master and the embodiment of every reason that adolescents of the postwar years turned to it in favor of the cheerfully torpid pop music … to which their parents were listening. —David Hajdu, New York Review of Books, 9 Oct. 2003

  5. When left unused, make-up has a tendency to dry out because any water or other volatile substances it contains evaporate. —Barry Fox, New Scientist, 9 Aug. 2003

  6. The stock market can be very volatile.

  7. She is a volatile woman.

  8. The protests are increasing, creating a volatile situation in the capital.

Did You Know?

Volatile was originally for the birds - quite literally. Back in the 14th century, volatile was a noun that referred to birds (especially wild fowl) or other winged creatures, such as butterflies. That's not as flighty as it sounds. Volatile traces back to the Latin verb volare, which means "to fly." By the end of the 16th century, people were using volatile as an adjective for things that were so light they seemed ready to fly. The adjective was soon extended to vapors and gases, and by the early 17th century, volatile was being applied to individuals or things as prone to sudden change as some gaseous substances. In recent years, volatile has landed in economic, political, and technical contexts far flown from its avian origins.

Origin of volatile

French, from Latin volatilis, from volare to fly

First Known Use: 1605

Other Chemical Engineering Terms



noun vol·a·tile \ˈvä-lə-təl, especially British -ˌtī(-ə)l\

Simple Definition of volatile

  • : a chemical or compound that changes into a gas easily

Source: Merriam-Webster's Learner's Dictionary

Full Definition of volatile

  1. :  a substance that is readily vaporizable at relatively low temperature :  a volatile substance

Origin of volatile

(see 1volatile)

First Known Use: 1686

Other Chemical Engineering Terms

VOLATILE Defined for Kids


adjective vol·a·tile \ˈvä-lə-təl\

Definition of volatile for Students

  1. 1 :  easily becoming a gas at a fairly low temperature <volatile solvents>

  2. 2 :  likely to change suddenly <a volatile temper>

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