- If you are certain of something, you believe it to be true without doubt.
- If something is certain, it will happen without doubt.
- If you make certain of something, you check that it is true or correct.
- (indefinite) (plural) Used to talk about groups or individuals without saying exactly which one(s).
- Certain problems can be solved with very simple math.
- Her job gave her a certain freedom.
- Certain of the members did not agree.
- Used to mean only one fits or applies; in other words, specific.
- I'm not looking for a certain kind of car, not just any kind.