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instable

American  
[in-stay-buhl] / ɪnˈsteɪ bəl /

adjective

  1. not stable; unstable.


instable British  
/ ɪnˈsteɪbəl /

adjective

  1. a less common word for unstable

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of instable

First recorded in 1375–1425; late Middle English word from Latin word instabilis. See in- 3, stable 2


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.

See Examples For:

Moreover, the conflict is becoming more drawn out, and even if it subsides there is a risk of an instable resolution where Iranian nuclear material and know-how leaks out to hostile groups around the Gulf.

From MarketWatch ● Mar. 10, 2026

But they’re still a little too instable in some areas to pull through and play to the level of their talent.

From Washington Post ● May 15, 2017

Their properties seemed equally consistent with the notion that an instable hydrogen atom oscillates inside of them, or that they are instable mixtures of two bodies.

From Pragmatism by William James

Yet I suspect my reformation, like most others of the kind, will prove instable as "the baseless fabric of a vision," unless I banish myself entirely from her society.

From The Coquette The History of Eliza Wharton by Hannah Webster Foster

The resultant situation, being profoundly unsatisfactory, would also be instable.

From Essays in Radical Empiricism by William James

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