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

Hundreds of climbers are attempting to scale Mount Everest despite high costs and an unstable ice block on the key trail.

From Los Angeles Times • May 27, 2026

The researchers carried out what may be the most detailed simulation yet of magnetic fields interacting with unstable velocity gradients.

From Science Daily • May 26, 2026

Other investigators point to the fact that the chromosomes in cancer tissue are unstable; they tend to be broken or damaged, the number may be erratic, there may even be double sets.

From "Silent Spring" by Rachel Carson

Vocabulary lists containing unstable

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