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.

They were more resistant to drying out, which would have been crucial in the dry and unstable climate following the mass extinction.

From Science Daily • Apr. 14, 2026

When recycled materials are stranded because of onerous trade restrictions, the result is lower investment, fewer jobs for American workers and unstable supply of feedstock for U.S. manufacturing.

From The Wall Street Journal • Apr. 14, 2026

Maybe she’s concerned that he could become financially unstable and a burden to her if he gives away too much.

From MarketWatch • Apr. 13, 2026

They also share other concerns: militants and the "unstable" Afghanistan.

From BBC • Apr. 10, 2026

In fact, it could well be the case that life, once it becomes complex, is inherently unstable and will self-destruct within a few thousand years.

From "Innumeracy: Mathematical Illiteracy and Its Consequences" by John Allen Paulos

Vocabulary lists containing unstable

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Engineering - Introductory

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Civil Engineering

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