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.

Even so, researchers have struggled to fully understand how these molecules form because many of the key intermediate stages are highly unstable and disappear almost instantly.

From Science Daily • May 22, 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

"Coming from a financially unstable background I was a perfect target for coercion," she added, during the tearful testimony.

From BBC • May 13, 2026

“So in an unstable composition, I could have Lil floating away to New Zealand.”

From "Okay for Now" by Gary D. Schmidt

Vocabulary lists containing unstable

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