adj C1 Advanced Uncommon

unsustainable

Unsustainable (adj) means not able to be kept up or maintained over time, especially without causing harm. Example: “The company's spending was unsustainable and it went bankrupt within a year.”

adj

Not able to be kept up or maintained over time, especially without causing harm.

"The company's spending was unsustainable and it went bankrupt within a year."

"Overfishing has pushed the industry toward unsustainable practices."

How to use unsustainable

Learner’s notes

In plain EnglishCan't continue like this without something breaking down — often used about the environment, finances, or workload.

Common pairings

unsustainable growth unsustainable debt environmentally unsustainable

Word forms

more unsustainable comparative, unsustainables plural, most unsustainable superlative

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The company's spending was _____ and it went bankrupt within a year.

Rhymes for unsustainable

able fable cable table viable liable stable tenable parable affable amiable notable

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Frequently asked questions

What does “unsustainable” mean?

The word “unsustainable” means not able to be kept up or maintained over time, especially without causing harm. In plain terms, can't continue like this without something breaking down — often used about the environment, finances, or workload.

How do you use “unsustainable” in a sentence?

Here is “unsustainable” used in a sentence: “The company's spending was unsustainable and it went bankrupt within a year.”

What part of speech is “unsustainable”?

“Unsustainable” is an adjective.

Is “unsustainable” a common word?

“Unsustainable” is an uncommon word in modern English, usually learned at around the C1 level.

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