Cool MateExtension vs Supplement
When to use each in English, with meaning, register, and examples.
Extension
Supplement
| Extension | Supplement | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/ɪkˈstenʃn/"]/🇺🇸 /["/ɪkˈstenʃn/"]/ | 🇬🇧 /["/ˈsʌplɪmənt/"]/🇺🇸 /["/ˈsʌplɪmənt/"]/ |
| Meaning | An addition to something, like a part that helps it work better. | Something added to help or improve something else. |
| Example | The deadline for the project got an extension of two weeks. | The textbook serves as a supplement to the main course material. |
| Register | Neutral | Neutral |
| How common | Top 2,000 (common) | Beyond 10,000 (less common) |
| CEFR level | B2 | C1 |
| Part of speech | noun | noun |
| Collocations | considerable, great, major, planned, proposed, home, add, build, extension to, planned, proposed, home, add, build, extension to, one-week, two-year, etc., apply for, ask for, request, planned, proposed, home, add, build, extension to, considerable, great, major, planned, proposed, home, add, build, extension to | useful, valuable, colour/color, provide (somebody/something with), add, take, supplement to, useful, valuable, colour/color, provide (somebody/something with), add, take, supplement to, useful, valuable, colour/color, provide (somebody/something with), add, take, supplement to, additional, extra, $100, add, charge, carry, be payable, at a supplement, supplement for, supplement on |
| Antonyms | restriction, limitation | reduction, diminution, lessening |
| Common mistakes | Confused with 'extent' — make sure to use the right context., Using 'extension' when 'addition' is more appropriate., Mispronouncing it as 'extention' instead of 'extension'. | Confused with 'complement', which means something that completes another., Using it as a verb when referring to physical items instead of additional support. |
| Usage notes | Commonly used in business and technology contexts. Avoid using it in very casual conversations. It's appropriate when discussing things like phone numbers or deadlines. | Used in contexts related to health, nutrition, and finance. Avoid in casual conversations unless discussing specific dietary needs or financial advice. |
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Frequently asked questions: Extension vs Supplement
What's the difference between Extension and Supplement?
Extension: An addition to something, like a part that helps it work better. Supplement: Something added to help or improve something else.
Which is more common: Extension and Supplement?
Extension is the most common in everyday English.
Which is more advanced: Extension and Supplement?
Supplement is the highest level, at C1, on the CEFR scale.
Are Extension and Supplement the same CEFR level?
Extension: B2, Supplement: C1 on the CEFR scale.
What part of speech are Extension and Supplement?
Extension: noun, Supplement: noun.
Can you show an example of each?
Extension: The deadline for the project got an extension of two weeks. Supplement: The textbook serves as a supplement to the main course material.
Can I use Extension and Supplement interchangeably?
Not always. Extension and Supplement are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.