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.

It can become unstable and demand enormous computing resources.

From Science Daily • May 6, 2026

But for someone unstable, hearing it often enough can lower the psychological barrier to acting.

From The Wall Street Journal • Apr. 27, 2026

A huge, unstable chunk of glacier is blocking the route up Mount Everest from Base Camp in Nepal just as peak climbing season gets under way in the Himalayas.

From BBC • Apr. 23, 2026

Applegate in March released “You With the Sad Eyes,” detailing everything from her unstable childhood to her decades-spanning acting career and the health issues that have plagued it.

From Los Angeles Times • Apr. 20, 2026

They kept the papacy weak and unstable, standing with their weapons in hand right under the eyes of the Pope.

From "The Prince" by Niccolò Machiavelli

Vocabulary lists containing unstable

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