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.

"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

Watch the NYU Stern School of Business professor and author talk about how to find a job in an unstable economy.

From The Wall Street Journal • May 28, 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

Their deeds would bring peace to an unstable world, preserved in legend among the stars.

From "The Reader" by Traci Chee

Vocabulary lists containing unstable

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