Your best definitely synonym changes when you are answering a question, stating a fact or stressing a point. Certainly, absolutely, undoubtedly, clearly and for sure are the five most useful swaps.
Definitely turns up constantly in student writing, and it often adds nothing. Below you can see which replacement sounds right in a quick reply, which one belongs in a report, and when the smart move is to cut the word out completely.
Swatch at a glance
Best swaps
certainly, absolutely, undoubtedly, clearly, for surePart of speech
AdverbMost casual
for sure, totally, you betMost formal
unquestionably, indisputably, undoubtedlyAntonyms
possibly, maybe, perhapsWatch out
Defiantly is a different word meaning rebelliously. Spell checkers will not always catch the slip.Related forms
definite, definitive
Four jobs for a definitely synonym
Most sentences with definitely fall into one of these groups.
| Job | Replacements | Example |
|---|---|---|
| States a fact with no doubt | certainly, undoubtedly, surely | Ravi is undoubtedly our strongest applicant. |
| Answers yes | absolutely, of course, for sure | Coming tonight? Of course. |
| Says it is plain to see | clearly, obviously, noticeably | The room is noticeably colder. |
| Confirms a plan | for certain, firmly, without fail | The shop will open on the first without fail. |
Saying definitely as a one-word answer
When a friend asks if you want pizza, a single word does the work. Absolutely is warm and enthusiastic. For sure and totally are relaxed and young-sounding. Of course can sound slightly cool if the question was not obvious, so watch your tone. By all means grants permission rather than agreeing: Can I borrow this? By all means.
A manager emails: "Can you join the call at four?" Replying "Definitely" is fine, but "Certainly, I will be there" looks more polished in an early exchange with a new contact.
Strength from maybe to unquestionably
Think of certainty as a dial. Maybe and possibly sit at the bottom, probably and likely in the middle, and definitely near the top. Above it sit unquestionably and indisputably, which claim nobody could reasonably argue. Use those only when you have proof, because a reader who disagrees will stop trusting you.
Note that the colored strip near the title is ordered by register, casual to formal, not by strength. For sure and unquestionably are about equally certain; they simply suit different rooms.
Before and after swaps
- This is definitely the right choice becomes this is clearly the right choice.
- I will definitely call you becomes I will call you for certain.
- The results were definitely better becomes the results were noticeably better.
- He is definitely talented becomes he is undoubtedly talented.
- We should definitely meet again becomes we really should meet again.
In essays, prove it instead
Teachers often circle definitely because it asserts without showing. Compare the policy definitely failed with the policy failed: crime rose for three straight years. The second needs no adverb. When you do want one, clearly and undoubtedly sound measured, and evidently signals that the evidence points one way. Our transition words guide offers further tools for building an argument.
Definitely, defiantly, definitively
Defiantly means in a rebellious way, so she defiantly agreed paints a strange picture. Definitively means in a final, authoritative way: a study can answer a question definitively. That is narrower than definitely, which only means without doubt. Also note the spelling: there is an i after the n, not an a.
Opposites of definitely
When you are not sure, choose possibly, perhaps or maybe for low confidence and probably for a fair guess. I will probably be late is honest and kind to the person waiting. For the adjective idea of being sure, see certain synonyms.
Frequently asked questions
Which definitely synonym suits formal writing?
Certainly and undoubtedly are the best formal choices. Unquestionably is stronger but should be backed by evidence.
How do people say definitely in a text message?
For sure, totally, absolutely and you bet all sound natural in a quick message. Choose whichever matches your usual voice with that person.
Is absolutely stronger than definitely?
In replies they are close, but absolutely sounds more enthusiastic. Inside a sentence, absolutely often modifies adjectives, as in absolutely right, where definitely would feel weaker.
What is the difference between definitely and definitively?
Definitely means without doubt. Definitively means in a final, conclusive way, often about an answer, ruling or study.
Which adverbs mean the reverse of definitely?
Possibly, maybe and perhaps sit at the other end. Probably sits in between, showing some confidence but not certainty.
Should I use definitely in an essay?
Use it rarely. Evidence convinces readers more than adverbs, and clearly or undoubtedly sound more academic when you need one.