UNSUSTAINABLE Synonyms: 26 Similar and Opposite Words

unsustainable

adjective

Definition of unsustainable

as in unsupportable

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Example Sentences

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.

Recent Examples of unsustainable The number of satellites, many experts say, is already bordering on unsustainable. — Jonathan O'Callaghan, Scientific American, 18 Aug. 2026 Add the cost of tires, consumables, a thirsty engine, and the fact that cars are all so ludicrously expensive to begin with these days, and soon the whole thing starts to look unsustainable. — Jonathan M. Gitlin, ArsTechnica, 17 Aug. 2026 The 11-year-old’s parents, Breann and Austin Tanton, were initially driving around 1,000 miles between Denham Springs and Cincinnati for the treatment, but the expense became unsustainable. — Latoya Gayle, PEOPLE, 15 Aug. 2026 This unsustainable mismatch must come into balance, one way or another. — Matt Egan, CNN Money, 13 Aug. 2026 See All Example Sentences for unsustainable

Recent Examples of Synonyms for unsustainable

Adjective

Currah’s opinion piece is wrong on the facts, the law, and the science, and reaches unsupportable conclusions.

— Paisley Currah, The New York Review of Books, 18 Dec. 2025
The venerable but troubled outlet has been for sale since its previous owners ran up unsupportable debts and were removed in 2023.

— Tom Chivers, semafor.com, 24 Nov. 2025

Definition of unsupportable

Adjective

Such a mind might fail an unverifiable consciousness test at the same time that its persistent interests start to boldly assert themselves.

— Andréa Morris, Forbes.com, 10 Aug. 2026
The most reliable move when labels feel unverifiable is to buy directly from a farmer or producer who can describe their practices.

— Anne Wolf, Martha Stewart, 26 July 2026

Definition of unverifiable

Adjective

Without that data, the patterns become invisible — or at least, unprovable.

— Maia Niguel Hoskin, Forbes.com, 25 June 2026
The meat of the documentary is the different SNL presidents talking about their individual impressions, their origins and their causally unprovable impacts on the perception of those presidents.

— Daniel Fienberg, HollywoodReporter, 10 June 2026

Definition of unprovable

Browse Nearby Words

unsuspicious

unsustainable

unswathe

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“Unsustainable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unsustainable. Accessed 27 Aug. 2026.

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Synonyms of unsustainable

adjective

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