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

Today many are struggling under the unsustainable repercussions of applying an industrial-era measure of productivity, namely dividing output by hours, to our modern knowledge economy. —Joe O’Connor, Time, 13 Jan. 2026

But Whipple said the time, cost and energy to keep the park going are unsustainable. —Judith Kohler, Denver Post, 12 Jan. 2026

Economists as well as Fed Chair Jerome Powell have said that model will be unsustainable in the long run, risking widening wealth inequality or a broader economic downturn if the wealthy are unable to maintain their spending habits. —Tristan Bove, Fortune, 12 Jan. 2026

Indiana football is everything right now, representing at once the enhancement of the college football product on the field and the unsustainable reality off it. —Joe Rexrode, New York Times, 11 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