instability

American  

[in-stuh-bil-i-tee] / ˌɪn stəˈbɪl ɪ ti /

noun

• instabilities
  plural

1. the quality or state of being unstable; lack of stability or firmness.

2. the tendency to behave in an unpredictable, changeable, or erratic manner.

   emotional instability.

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instability British  

/ ˌɪnstəˈbɪlɪtɪ /

noun

1. lack of stability or steadiness

2. tendency to variable or unpredictable behaviour

3. physics a fast growing disturbance or wave in a plasma

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Other Word Forms

Noun Inflected Forms

• instabilities
  plural

Etymology

Origin of instability

1375–1425; late Middle English instabilite < Latin instabilitās. See in- ³, stability

Explanation

Instability is the quality of not being stable, balanced, or predictable. If you've ever walked out onto a diving board, you've probably noticed its instability — meaning the board bends and bounces as you move. Instability comes from the Middle French word instabilite, meaning "unsteadiness." Instability can refer to objects that are not stable, but it can also describe unpredictable situations or relationships. For example, you might hear people talk about economic instability. Or if your behavior at school grows erratic and unpredictable, you might be asked to speak to a therapist about your psychological instability.

Example Sentences

See Examples For:

instability instabilities

Despite this conflict - and growing instability across the wider region - migrants still cross the Bab el-Mandeb Strait to Yemen driven by poverty, insecurity and the growing impacts of climate change.

From BBC ● Oct. 11, 2026

Scientists have long investigated the possibility of thermal "runaway" instability.

From Science Daily ● Oct. 10, 2026

It also often leads to housing instability, academic withdrawal, and family dissolution.

From Slate ● Oct. 8, 2026

Asian refiners are among those that might want to diversify their crude sources as a result of the instability in the Middle East.

From The Wall Street Journal ● Sep. 28, 2026

“But when things weren’t going well, they became signs of incompetence or instability on my part—even among employees and business partners.”

From "The Big Short" by Michael Lewis

Those conditions could provide exactly what is needed for Kelvin-Helmholtz instabilities to form.

From Science Daily ● Aug. 8, 2026

By developing a new high-density operating approach for EAST, the team showed that plasma density can be pushed well past long-standing empirical limits without triggering the disruptive instabilities that usually end experiments.

From Science Daily ● Jan. 4, 2026

Combining high-speed synchrotron X-ray imaging, theoretical analysis and numerical simulation, the researchers revealed the defect mitigation mechanisms, which involve phenomena that reduce instabilities in the laser powder bed fusion process.

From Science Daily ● Nov. 22, 2024

If instead the researchers can improve the model's ability to recognize the precursors to these harmful instabilities, it could be possible to optimize the system without encountering a single edge burst.

From Science Daily ● Jun. 5, 2024

France has struggled since 1958—arguably with success—to construct a presidential democracy resistant to the severe instabilities inherent in the parliamentary democracy of early 20th century France.

From The 1999 CIA World Factbook by United States. Central Intelligence Agency

Related Words

• anxiety
• fluctuation
• insecurity
• uncertainty
• volatility
• vulnerability
• weakness