Definitions

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.

Maybe she’s concerned that he could become financially unstable and a burden to her if he gives away too much.

From MarketWatch • Apr. 13, 2026

With only six, carbenes are highly unstable and react almost instantly with their surroundings.

From Science Daily • Apr. 11, 2026

They also share other concerns: militants and the "unstable" Afghanistan.

From BBC • Apr. 10, 2026

Researchers found that Latino students faced myriad challenges, including immigration issues, English proficiency and unstable housing that is linked to their parents’ employment status.

From Los Angeles Times • Apr. 1, 2026

Everything, for a moment—mirror, ceiling, floor—was unstable and radiant as a dream.

From "The Secret History" by Donna Tartt

Vocabulary lists containing unstable

100 SAT Words Beginning with "U"

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Engineering - Introductory

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Civil Engineering

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