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.

There are unstable layers of debt at the firm, fund and investor level.

From MarketWatch • May 20, 2026

"We are asking for your support in adopting several cost containment measures to help our company navigate this unstable situation," it said.

From Barron's • May 19, 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

She expects an unstable climate to usher in an age of private weather control.

From The Wall Street Journal • Apr. 30, 2026

But theirs was not a natural isotope, it was an unstable isotope of phosphorus created in their laboratory.

From "Big Science" by Michael Hiltzik

Vocabulary lists containing unstable

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Engineering - Introductory

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