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.

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

From The Wall Street Journal • Apr. 30, 2026

While fluid membranes support fusion, they can also become unstable during freeze-thaw-induced stress, leading to leakage.

From Science Daily • Apr. 29, 2026

Some owners report losses of 25-40% since the war began, and say they are uncertain how long they can continue if supplies remain unstable.

From BBC • Apr. 28, 2026

Instead, Perez sees a web of failed systems: narrow services for military veterans, limited mental health treatment options, insufficient gun restrictions and not enough protections for children living with unstable parents.

From Los Angeles Times • Apr. 24, 2026

All you need is the evidence of the ECG, blood pressure, fluid in the lungs, and unstable angina.

From "Blink" by Malcolm Gladwell

Vocabulary lists containing unstable

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