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.

This is the 17th Ebola outbreak to hit the DRC, a vast and unstable central African country of more than 100 million people.

From Barron's • Jun. 8, 2026

But over the short and even intermediate terms, lasting not just several years but decades, gold’s correlation to inflation is unstable.

From MarketWatch • Jun. 8, 2026

The governor said the tragedy underscored the "vulnerability of young people engaged in migratory and cross-border economic activities, often forced to pass through unstable areas in order to survive or seek better living conditions".

From BBC • Jun. 5, 2026

Because these intermediate phases are highly unstable, they have been extremely difficult to observe directly.

From Science Daily • May 30, 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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