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.

Even so, researchers have struggled to fully understand how these molecules form because many of the key intermediate stages are highly unstable and disappear almost instantly.

From Science Daily • May 22, 2026

A Hypershell spokesman said that a snug, proper fit and a lower level of assistance can help on unstable terrain.

From The Wall Street Journal • May 21, 2026

There are unstable layers of debt at the firm, fund and investor level.

From MarketWatch • May 20, 2026

"We are asking for your support in adopting several cost containment measures to help our company navigate this unstable situation," it said.

From Barron's • May 19, 2026

We could not use the second level because the floors were unstable.

From "The Circuit: Stories from the Life of a Migrant Child" by Francisco Jiménez

Vocabulary lists containing unstable

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Engineering - Introductory

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