instability
Americannoun
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instabilities
plural
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the quality or state of being unstable; lack of stability or firmness.
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the tendency to behave in an unpredictable, changeable, or erratic manner.
emotional instability.
noun
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lack of stability or steadiness
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tendency to variable or unpredictable behaviour
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physics a fast growing disturbance or wave in a plasma
Other Word Forms
Noun Inflected Forms
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.
Vocabulary lists containing instability
Southeast Asia - Middle School
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Southeast Asia - High School
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Second Democratic Debate 20 words
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
The country has hundreds of projects in development, but those plans are now threatened by growing instability in the Himalayas.
From The Wall Street Journal ● Sep. 11, 2026
Sam Gardner lived in 15 foster homes between the ages of three and 17, and said the instability was a "big challenge".
From BBC ● Sep. 9, 2026
Conventional controllers cannot identify this instability until it has already begun.
From Science Daily ● Sep. 6, 2026
A major earthquake in 2015 may also have contributed to longer-term instability.
From Barron's ● Sep. 4, 2026
“I know what removal would mean. I’m not a child. It would mean complete instability, with no nonimaginary solutions to the positronic Field Equations.”
From "I, Robot" by Isaac Asimov
Those conditions could provide exactly what is needed for Kelvin-Helmholtz instabilities to form.
From Science Daily ● Aug. 8, 2026
These persistent instabilities can affect everything from uplift and erosion to inland volcanic patterns, even in regions considered geologically stable.
From Science Daily ● Nov. 25, 2025
By measuring the beam's shape and the magnetic fields it generated, the researchers were able to determine whether plasma instabilities could be strong enough to disrupt the beam's flow.
From Science Daily ● Nov. 7, 2025
However, the high-confinement mode has historically come hand-in-hand with instabilities at the plasma's edge, a challenge that has required fusion researchers to find creative workarounds.
From Science Daily ● Jun. 5, 2024
When we were unable to contact Standskill, we sought to contact you psionically last night, but found that your mind was a completely unreadable jumble of nightmares, filled with phobias and instabilities.
From The Psilent Partner by John Victor Peterson
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
