clear up = make something clear, understand fully and solve it
- I 'd like to clear something up: I 'm not going to pay for the car if you take it without my permission again.
- Before you start working here, there are a few points I would like to clear up.
- I have come to clear up the misunderstanding. I never said you were lazy!
- The two students were fighting and the teacher rushed to clear the matter up.
- We 'll need a professional detective to clear this mystery up, to clear this confusion up!