Cool MateDefinitely vs Of course
When to use each in English, with meaning, register, and examples.
Definitely
Top 1,000 (very common)A2adverb
Of course
Top 1,000 (very common)
| Definitely | Of course | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/ˈdefɪnətli/"]/🇺🇸 /["/ˈdefɪnətli/"]/ | 🇬🇧 //əv kɔːs//🇺🇸 //əv kɔrs// |
| Meaning | For sure, without a doubt | Definitely, it's obvious. |
| Example | I definitely remember sending the letter. | Are you joining us for dinner tonight? Of course! |
| Register | Neutral | Neutral |
| How common | Top 1,000 (very common) | Top 1,000 (very common) |
| CEFR level | A2 | - |
| Part of speech | adverb | |
| Collocations | definitely agree, definitely believe, definitely know | of course not, of course yes, of course you can, of course it is |
| Antonyms | doubtfully, uncertainly | - |
| Common mistakes | Often confused with 'defiantly' which means resisting authority., Sometimes spelled incorrectly as 'definately'. | Using it in formal writing where a different expression is needed., Confusing it with other affirmations like 'certainly' or 'definitely'. |
| Usage notes | Use 'definitely' to emphasize certainty. It fits well in both spoken and written English. Avoid using it in overly formal contexts where alternatives like 'certainly' might be more suitable. | Used in informal and formal situations to affirm something obvious. Avoid in highly formal writing. |
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Frequently asked questions: Definitely vs Of course
What's the difference between Definitely and Of course?
Definitely: For sure, without a doubt Of course: Definitely, it's obvious.
Can you show an example of each?
Definitely: I definitely remember sending the letter. Of course: Are you joining us for dinner tonight? Of course!
Can I use Definitely and Of course interchangeably?
Not always. Definitely and Of course 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.