unsustainable

adjective

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

: not capable of being prolonged or continued : not sustainable

unsustainable agricultural practices

unsustainable growth

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

There was some speculation — and accompanying concern from fans — that that could happen at the start of the offseason given owner Hal Steinbrenner’s prior remarks about such a figure being unsustainable. —Gary Phillips, New York Daily News, 22 Jan. 2026

Dark-side leadership, though generally unsustainable, can appear effective in isolated episodes, particularly in low-integrity contexts. —Mary Crossan, Forbes.com, 21 Jan. 2026

The current trajectory for college sports is unsustainable. —Sheldon H. Jacobson, Chicago Tribune, 21 Jan. 2026

Just as too-tight policy can needlessly slow growth and add to unemployment, ​too-loose policy pushes the economy beyond its productive capacity, lowering unemployment to an unsustainable level and driving up wages and prices. —Howard Schneider, USA Today, 19 Jan. 2026

Word History

First Known Use

circa 1677, in the meaning defined above

Rhymes for unsustainable

• attainable
• explainable
• maintainable
• obtainable
• sustainable
• ascertainable
• unattainable
• unexplainable
• unobtainable
• trainable