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.

There are 82 confirmed cases and seven confirmed deaths in the vast, unstable DRC, alongside almost 750 suspected cases and 177 suspected deaths, the WHO said on Friday.

From Barron's • May 23, 2026

A Hypershell spokesman said that a snug, proper fit and a lower level of assistance can help on unstable terrain.

From The Wall Street Journal • May 21, 2026

Also, I have flashbacks of panic due to his previously unstable financial behavior.

From MarketWatch • May 16, 2026

Another said they became emotionally unstable, had nightmares and spent most of their days in their bedroom.

From BBC • May 12, 2026

Watson knew immediately that the structure would not work: it was energetically unstable.

From "The Gene" by Siddhartha Mukherjee

Vocabulary lists containing unstable

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