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.

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

"Rivers that are normally completely frozen have overflowed where they hadn't historically," he told the BBC, causing layered, unstable ice sheets that are hazardous to travel over in winter months.

From BBC • Apr. 12, 2026

With only six, carbenes are highly unstable and react almost instantly with their surroundings.

From Science Daily • Apr. 11, 2026

“Maybe I’ve made it my business. Maybe I think you’re unstable and the best thing would be for you to back away from Immie and get some help for your mental problems.”

From "Genuine Fraud" by E. Lockhart

Vocabulary lists containing unstable

100 SAT Words Beginning with "U"

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Engineering - Introductory

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Civil Engineering

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