unstable

[uhn-stey-buhl] / ʌnˈsteɪ bəl /

ADJECTIVE

doubtful

Synonyms

STRONGEST

ambiguous changeable erratic fickle insecure irrational precarious risky rocky sensitive shaky slippery ticklish tricky uncertain unpredictable unsettled unsteady volatile weak wobbly

WEAK

borderline capricious dizzy dubious fitful fluctuating giddy inconsistent inconstant lubricious mercurial mobile movable moving mutable not fixed rickety shifty suspect teetering temperamental untrustworthy vacillating variable wavering weaving wiggly

Antonyms

STRONGEST

certain clear confident constant definite dependable easy firm guarded happy predictable protected reliable safe secure sound stable steady strong sure unchanging unshaky

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.

Also, I have flashbacks of panic due to his previously unstable financial behavior.

From MarketWatch • May 16, 2026

She did some moves that were pretty irrational, and she would have times where she would act on impulse, and it became more and more unstable and unsafe.

From Los Angeles Times • May 13, 2026

Mohammadi's Paris-based husband said "she is not in a favourable general condition" and that "her status remains unstable", in a statement over the weekend.

From BBC • May 10, 2026

Developing a robust offshore wind industry provides resilience in the face of an unstable global energy market.

From Salon • May 9, 2026

The nearest likely candidate he added, is Betelgeuse, whose various sputterings have for years suggested that something interestingly unstable is going on there.

From "A Short History of Nearly Everything" by Bill Bryson

Vocabulary lists containing unstable

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