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.

In April, a record 35 candidates ran for president of the chronically unstable Andean nation, which has burned through eight presidents in the past decade, four of whom were impeached.

From Barron's • May 8, 2026

For them, giving the military more legitimacy is not about ignoring pacifism, but about making sure the country can survive an increasingly unstable world.

From BBC • May 7, 2026

From above, the atmosphere revealed just how unstable conditions had become, with striking cloud formations spreading over the nearby ocean.

From Science Daily • May 6, 2026

She expects an unstable climate to usher in an age of private weather control.

From The Wall Street Journal • Apr. 30, 2026

When a neutron traveling at just the right speed strikes the nucleus of a uranium 235 atom, it is absorbed and the atom becomes even more unstable.

From "Meltdown" by Deirdre Langeland

Vocabulary lists containing unstable

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