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

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

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

Or they may simply feel "unstable"; if you hear a chord with a dissonance in it, you may feel that the music is pulling you towards the chord that resolves the dissonance.

From "Understanding Basic Music Theory" by Catherine Schmidt-Jones and Russel Jones

Vocabulary lists containing unstable

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