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.

Instead, Perez sees a web of failed systems: narrow services for military veterans, limited mental health treatment options, insufficient gun restrictions and not enough protections for children living with unstable parents.

From Los Angeles Times • Apr. 24, 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

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

Interestingly, 12 of the 14 known circumbinary planets orbit just beyond this unstable region.

From Science Daily • Apr. 19, 2026

She wondered why her heart now felt too large for her body, and why she was so unstable in her shoes.

From "Throne of Glass" by Sarah J. Maas

Vocabulary lists containing unstable

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Engineering - Introductory

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