IELTS Speaking · Vocabulary
sustainable
adjective/səˈsteɪnəbl/Band 6
Last updated 21 July 2026
In short
“sustainable” is a Band 6 adjective that means able to continue over time without depleting natural resources or harming the environment. Below you'll find its pronunciation, natural example sentences, synonyms and antonyms, and the collocations that help you use it accurately in the IELTS Speaking test.
Meaning
Able to continue over time without depleting natural resources or harming the environment.
Example sentences
Natural, spoken examples at the level an examiner rewards.
- “We need a more sustainable approach to farming.”
- “The city aims for sustainable growth.”
Synonyms & antonyms
Synonyms
eco-friendlyrenewableviable
Antonyms
unsustainablewasteful
Collocations & common phrases
Word partners that make your usage sound natural — the difference between knowing a word and using it well.
Collocations
sustainable developmentsustainable energyenvironmentally sustainable
Common phrases
in the long term
Related words
Explore more vocabulary
Frequently asked questions
What does “sustainable” mean?
Able to continue over time without depleting natural resources or harming the environment.
How do you use “sustainable” in a sentence?
For example: “We need a more sustainable approach to farming.”
What are some synonyms for “sustainable”?
Synonyms include eco-friendly, renewable, viable.
Is “sustainable” good vocabulary for IELTS Speaking?
Yes. It is Band 6 vocabulary, and collocations such as sustainable development, sustainable energy, environmentally sustainable help you use it naturally. Reaching for precise, less common words like this is exactly what lifts your Lexical Resource score.
Next step
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