Synonyms & Antonyms of unstable

1 not being in or able to maintain a state of balance
  • the minute we put the books down on the unstable desk, the whole stack went crashing to the floor

Synonyms for unstable

Words Related to unstable

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Antonyms for unstable

3 not staying constant
  • unstable temperatures are not ideal storage conditions for wine

Synonyms for unstable

Words Related to unstable

Near Antonyms for unstable

Antonyms for unstable

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Frequently Asked Questions About unstable

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

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Time Traveler for unstable

Time Traveler

The first known use of unstable was in the 13th century

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Cite this Entry

“Unstable.” Thesaurus, Merriam-Webster, Accessed 20 Oct. 2021.

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More from Merriam-Webster on unstable

Nglish: Translation of unstable for Spanish Speakers


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