un·​sus·​tain·​able | \ ˌən-sə-ˈstā-nə-bəl \

Definition of unsustainable

: not capable of being prolonged or continued : not sustainable unsustainable agricultural practices unsustainable growth

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Other Words from unsustainable

unsustainability \ ˌən-​sə-​ˌstā-​nə-​ˈbi-​lə-​tē \ noun
unsustainably \ ˌən-​sə-​ˈstā-​nə-​blē \ adverb
an unsustainably high rate of growth

Examples of unsustainable in a Sentence

Recent Examples on the Web

And Illinois’ flat-rate income tax system, which turns 50 this year, is unsustainable, according to Pritzker, whose $3.2 billion net worth ranked him 251st on Forbes’ wealthiest 400 Americans last fall. John O'connor, The Seattle Times, "Gov. Pritzker gives Democrats near-record power in Illinois," 14 Jan. 2019 These programs depend on meticulous data input, which may prove unsustainable. Maya Wang, WSJ, "China’s Bumbling Police State," 26 Dec. 2018 For many fans of the sport, DPi cars should be an obvious addition to the French endurance race at Le Mans, particularly after the hybrid LMP1 class there proved to be financially unsustainable. Jonathan M. Gitlin, Ars Technica, "IMSA’s WeatherTech series is going great, but where does it go next?," 3 Sep. 2018 Meanwhile, a series of SEC filings has shown that the company is posting huge quarterly losses, leading to auditors suggesting its model is financially unsustainable. Tasha Robinson, The Verge, "The new MoviePass plan has arrived, and it’s weird," 16 Aug. 2018 However, that growth is likely unsustainable given low prices for Alberta crude oil, and the possibility the Alberta government orders production cuts to lift the price of Western Canadian Select. Kim Mackrael, WSJ, "Canada’s Economic Growth Slows Amid Lower Business Investment," 30 Nov. 2018 The current two-track system of global governance is unsustainable. Matthew Pennington, The Seattle Times, "At UN this year, it’s Trump versus the world," 25 Sep. 2018 But to some people, the trouble reinforced the notion that MoviePass’s business model is unsustainable, and that the company is doomed to implode any day now. Alissa Wilkinson, Vox, "MoviePass isn’t dead yet, but it’s banking on a risky strategy to stay afloat," 3 Aug. 2018 That puts India at the epicenter of a global conundrum: How to accommodate the escalating needs for electricity without setting off an unsustainable tidal wave of energy use? Russell Gold, WSJ, "Can India Afford to Cool Down?," 21 Nov. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'unsustainable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of unsustainable

circa 1677, in the meaning defined above

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Last Updated

22 Jan 2019

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Time Traveler for unsustainable

The first known use of unsustainable was circa 1677

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English Language Learners Definition of unsustainable

: not able to last or continue for a long time : not sustainable

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