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
ˌən-sə-ˌstā-nə-ˈbi-lə-tē How to pronounce unsustainable (audio)
noun
unsustainably
ˌən-sə-ˈstā-nə-blē How to pronounce unsustainable (audio)
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.
Europe’s social safety net has been on an unsustainable path for decades, and economists and some politicians have warned for years that the bill would eventually come due. — David Goldman, CNN Money, 20 Oct. 2026 Meanwhile, public debt is soaring, a development the IMF warns is unsustainable. — Justin Worland, Time, 17 Oct. 2026 That penchant for scoring first in matches is another unsustainable quirk muddying Chelsea’s statistical waters. — Conor O'Neill, New York Times, 15 Oct. 2026 Apple's new Apple TV 4K got a price hike from $199 to $299, and follows a similar price increase earlier this year, after Cook said that memory costs for Apple were unsustainable. — Kif Leswing, CNBC, 13 Oct. 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

Rhymes for unsustainable

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Browse Nearby Words

unsuspicious
unsustainable
unsustained
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Cite this Entry

“Unsustainable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unsustainable. Accessed 21 Oct. 2026.

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