unsustainable
un-suh-STAY-nuh-bul
/ˌʌnsəˈsteɪnəbl/
Not able to be maintained or continued at the current rate or level without causing irreversible harm or collapse.
Highlights an inevitable future breaking point if current practices are kept up.
The story behind the word. Latin 'subtinere' meant to support something heavy from beneath, like a pillar holding up a roof. Adding 'un-' and '-able' creates a word that describes an architectural or ecological roof whose pillars are rotting away—eventually, the whole structure must come crashing down.
Word relationships
- unviable: Unviable means incapable of working successfully at all, whereas unsustainable means it works now but will crash later.
- tenuous: Tenuous means weak or flimsy, while unsustainable focuses on the inability to keep going over time.
- sustainable: Sustainable means capable of being maintained indefinitely without destroying resources.
- viable: Viable means capable of living or succeeding over long periods.
Commonly confused with
- unsubstantiated: Unsubstantiated means unverified or unproven, while unsustainable means unable to be maintained.
Word family
- sustain (verb): To strengthen or support over time.
- sustainability (noun): The ability to be maintained at a steady rate without exhausting natural capital.
Collocations
- unsustainable growth
- unsustainable practices
- unsustainable pace
- unsustainable level
Example sentences
- "Relying on non-renewable energy sources is an unsustainable long-term strategy." Macroeconomics
Memory hook
UN-SUSTAINABLE = UN-able to SUB-tain (hold up) the strain. Unsustainable = Destined to collapse.
When not to use
Avoid using for minor inconveniences that can easily be patched; it refers to structural instability.
Fun facts
- Economist Herb Stein famously coined 'Stein's Law': 'If something cannot go on forever, it will stop.'—the ultimate definition of unsustainable!
Related words
Explore more words
sustainable, sustain, sustainability, sustained, irrevocable, inevitable
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