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.

Born in Los Angeles on June 1, 1926, Monroe had an unstable childhood spent between orphanages and foster homes.

From Barron's • Jun. 1, 2026

"I just wouldn't risk having an important video call," Rebecca says, citing how unstable the connection often is.

From BBC • May 30, 2026

Because these intermediate phases are highly unstable, they have been extremely difficult to observe directly.

From Science Daily • May 30, 2026

About 90,000 gallons of the chemical is left in the tank and remains unstable, complicating recovery efforts, said Scott Goldstein, chief of Cowlitz 2 Fire & Rescue.

From The Wall Street Journal • May 27, 2026

But if the building was too unstable to stand from all the bombs and the fire, how long until something else collapsed?

From "Time Bomb" by Joelle Charbonneau

Vocabulary lists containing unstable

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Engineering - Introductory

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