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.

At the heart of quantum computing are qubits, which offer the promise of answering questions that defeat today's machines, but are notoriously delicate and unstable.

From BBC • Jun. 2, 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

There are 82 confirmed cases and seven confirmed deaths in the vast, unstable DRC, alongside almost 750 suspected cases and 177 suspected deaths, the WHO said on Friday.

From Barron's • May 23, 2026

The naked singularities were unstable: the least disturbance would cause them either to disappear or to be hidden behind an event horizon.

From "A Brief History of Time: And Other Essays" by Stephen Hawking

Vocabulary lists containing unstable

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Engineering - Introductory

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Civil Engineering

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