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Synonym Chooser

How does the adjective unstable differ from other similar words?

Some common synonyms of unstable are capricious, fickle, inconstant, and mercurial. While all these words mean "lacking firmness or steadiness (as in purpose or devotion)," unstable implies an incapacity for remaining in a fixed position or steady course and applies especially to a lack of emotional balance.

too unstable to hold a job

When can capricious be used instead of unstable?

The synonyms capricious and unstable are sometimes interchangeable, but capricious suggests motivation by sudden whim or fancy and stresses unpredictability.

an utterly capricious critic

When would fickle be a good substitute for unstable?

The words fickle and unstable can be used in similar contexts, but fickle suggests unreliability because of perverse changeability and incapacity for steadfastness.

performers discover how fickle fans can be

When is inconstant a more appropriate choice than unstable?

The words inconstant and unstable are synonyms, but do differ in nuance. Specifically, inconstant implies an incapacity for steadiness and an inherent tendency to change.

an inconstant friend

When could mercurial be used to replace unstable?

Although the words mercurial and unstable have much in common, mercurial implies a rapid changeability in mood.

made anxious by her boss's mercurial temperament

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of unstable Violence is what grows in the vacuum left when schools lose funding, housing is unstable, mental health care is unavailable and jobs vanish. Chicago Tribune, 11 June 2025 In an era of such rapid and enormous change, the characteristics that defined an American, an American body, and, therefore, American citizenship itself were unstable and uncertain. Literary Hub, 9 June 2025 Lowers Risk of Chronic Disease Eggs are rich in antioxidants, which are plant compounds that reduce cell damage caused by unstable molecules called free radicals in the body. Carrie Madormo, Verywell Health, 6 June 2025 The California Coastal Commission approved emergency construction last month after several sections of the rail, which lie below bluffs, were deemed unstable and at immediate risk of landslide and coastal erosion. Christopher Buchanan, Los Angeles Times, 30 May 2025 See All Example Sentences for unstable
Recent Examples of Synonyms for unstable
Adjective
  • The camera swirls around the scene, unsteady and swift.
    Madison Bloom, Pitchfork, 16 May 2025
  • It’s maintained an idiosyncratic spirit all along, combining references from across rock history—a Bob Dylan harmonica line here, a Cars synth line there—with lyrics that unspool in unsteady, careening cadences.
    Spencer Kornhaber, The Atlantic, 22 May 2025
Adjective
  • But make no mistake: the situation remains extremely volatile.
    Robert Rapier, Forbes.com, 16 June 2025
  • Israel’s strikes on Iran and Tehran’s retaliation, which appeared to catch many world leaders unawares, is the latest sign of a more volatile world.
    Rob Gillies, Chicago Tribune, 15 June 2025
Adjective
  • But the event comes at a highly precarious time, amid nationwide protests which started in Los Angeles when people rallied against raids conducted by U.S. Immigration and Customs Enforcement (ICE).
    Callum Sutherland, Time, 11 June 2025
  • Put aside the dumb optics of Abrams tanks rolling through DC, this is happening at a precarious moment.
    Carlo Versano, MSNBC Newsweek, 10 June 2025
Adjective
  • Entrepreneurs who want to survive must meet our current reality by staying as flexible as the market is unpredictable.
    Cynthia Pong, Forbes.com, 8 June 2025
  • Netflix offers premium, brand-safe content in a streaming environment that’s becoming increasingly fragmented and unpredictable.
    Shannon Carroll, Quartz, 6 June 2025
Adjective
  • That means Juno’s radio transmissions will experience the Doppler effect, where the wavelength shifts slightly in response to Io’s uneven gravitational field.
    Robin Andrews, Wired News, 15 June 2025
  • Avoid wobbly or uneven fittings to keep everything centered.
    Elizabeth Fogarty, Better Homes & Gardens, 15 June 2025
Adjective
  • The implications were profound: With a lot of rocky material, tidal heating can make oceans of magma.
    Robin Andrews, Wired News, 15 June 2025
  • The first two miles are the hardest, composed of rocky stairs and switchbacks winding steeply up the side of the mountain.
    Eva Frederick, Travel + Leisure, 14 June 2025
Adjective
  • Vietnam is also dealing with a unbalanced gender ratio, partly because of a long-standing preferences for sons.
    Arkansas Online, Arkansas Online, 4 June 2025
  • Most important, the legislation is massively expensive and will add further to the debt/deficit at a time when both are already extremely unbalanced.
    Anne Marie D. Lee, CBS News, 21 May 2025

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Cite this Entry

“Unstable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unstable. Accessed 19 Jun. 2025.

More from Merriam-Webster on unstable

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