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.

Some owners report losses of 25-40% since the war began, and say they are uncertain how long they can continue if supplies remain unstable.

From BBC • Apr. 28, 2026

But for someone unstable, hearing it often enough can lower the psychological barrier to acting.

From The Wall Street Journal • Apr. 27, 2026

When the earth layers of the cliffside move, oxygen can interact with unstable compounds in the rocks — including iron sulfides — which produces a lot of heat during the oxidation process.

From Los Angeles Times • Apr. 24, 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

It looked shaky and unstable, so I slowed the car to a stop.

From "Just Mercy" by Bryan Stevenson

Vocabulary lists containing unstable

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Engineering - Introductory

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