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.

In April, a record 35 candidates ran for president of the chronically unstable Andean nation, which has burned through eight presidents in the past decade, four of whom were impeached.

From Barron's • May 8, 2026

It can become unstable and demand enormous computing resources.

From Science Daily • May 6, 2026

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

From The Wall Street Journal • Apr. 30, 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

“Maybe I’ve made it my business. Maybe I think you’re unstable and the best thing would be for you to back away from Immie and get some help for your mental problems.”

From "Genuine Fraud" by E. Lockhart

Vocabulary lists containing unstable

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Engineering - Introductory

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