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.
Musk is correct that the national debt trajectory is unsustainable on current trends. — Judi Willard, Baltimore Sun, 27 Oct. 2026 And restaurants that manage to find money in their budget can still face sudden, unsustainable increases. — Jen Christensen, CNN Money, 24 Oct. 2026 Anxiety over America’s build-out of data centers has reached Wall Street in recent days, kindling fears that the artificial intelligence boom is unsustainable. — Editorial Board, Washington Post, 23 Oct. 2026 The goal is to save money, cut back on overconsumption and be more mindful of wasteful and unsustainable shopping habits. — Margaret Cirino, NPR, 23 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

See All Rhymes for unsustainable

Browse Nearby Words

unsuspicious
unsustainable
unsustained
See all Nearby Words

Cite this Entry

“Unsustainable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unsustainable. Accessed 28 Oct. 2026.

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