unsustainable

adjective

un·​sus·​tain·​able ˌən-sə-ˈstā-nə-bəl How to pronounce unsustainable (audio)
Synonyms of unsustainablenext
: not capable of being prolonged or continued : not sustainable
unsustainable agricultural practices
unsustainable growth
unsustainability noun
unsustainably adverb
an unsustainably high rate of growth

Examples of unsustainable in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The question is whether there are too many companies raising at unsustainable valuations, and if venture capital is the right tool for tech that’s inextricably tied to national security. Allie Garfinkle, Fortune, 2 July 2026 MeVa's Administrator Noah Berger said the current system is unsustainable. Penny Kmitt, CBS News, 1 July 2026 The current system risks patient dissatisfaction if complex issues aren't addressed by doctors, and further physician disenfranchisement is unsustainable. Forbes.com, 30 June 2026 Recent attacks on the Dubna facility and on a major Moscow oil refinery typify distinct parts of the Ukrainian strategy to make the war unsustainable for the Russian dictator. Phillips Payson O’Brien, The Atlantic, 30 June 2026 See All Example Sentences for unsustainable

Word History

First Known Use

circa 1677, in the meaning defined above

Time Traveler
The first known use of unsustainable was circa 1677

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Cite this Entry

“Unsustainable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unsustainable. Accessed 5 Jul. 2026.

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