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.

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

By the time the doctor had logged there was no fetal heartbeat, the medical record shows, Crain was too unstable for surgery.

From Salon • Apr. 20, 2026

Klymenko described the man's mental state as "clearly unstable".

From BBC • Apr. 19, 2026

Despite extreme heat, unstable conditions, and long-lasting droughts, Lystrosaurus not only endured but flourished.

From Science Daily • Apr. 14, 2026

Other investigators point to the fact that the chromosomes in cancer tissue are unstable; they tend to be broken or damaged, the number may be erratic, there may even be double sets.

From "Silent Spring" by Rachel Carson

Vocabulary lists containing unstable

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