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 By 1910, the financial burden of rebuilding had become unsustainable, prompting Argentine to consolidate with Kansas City, Kansas. — Michelle Oliva-Espinosa, Kansas City Star, 18 July 2026 Social Security protects retirees from poverty, but at an unsustainable cost. — Daniel De Visé, USA Today, 16 July 2026 Fans will grumble if prem teams don’t feature in the league cup or teams with European football don’t play in the FA Cup, but the current schedule is unsustainable. — Nnamdi Onyeagwara, New York Times, 13 July 2026 For many residents in this district, housing costs have become unsustainable, with many renters spending over 50% of their income on housing alone according to the National Institutes of Health. — Dale V.c. Holness, Sun Sentinel, 9 July 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

Even if my archive was unverifiable or incongruous, the hazy, contradictory landscape of Goodman’s life was the truth of her existence.

— Literary Hub, Literary Hub, 13 May 2026
But MetroCard and cash payments were unverifiable for the teams, which are equipped with handheld readers that can ascertain whether an OMNY card, bank card or smartphone has recently been used to pay a fare.

— Evan Simko-Bednarski, New York Daily News, 27 Apr. 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 25 Jul. 2026.

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Synonyms of unsustainable

adjective

Example Sentences

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