v.1. To remove obstructions, unwanted objects, or imperfections from something: Could you help me clear up the table after dinner? The allergy medication cleared my sinuses up.
2. To remove some obstructions, unwanted objects, or imperfections: Firefighters quickly cleared up the accident, and traffic returned to normal. When I got poison ivy, the doctor gave me a medicinal cream to clear it up.
3. To become free of obstructions, unwanted objects, or imperfections: My skin has cleared up since I started using that acne medication.
4. To go away; disappear: I hope the traffic clears up before I have to drive home.
5. To clarify something: This article should clear up some of the confusion surrounding my new theory. The origin of the artifact remained a mystery, and we hoped that the professor could clear it up.
6. To become more apparent or easily perceptible: As we discussed the issue, it began to clear up.
7. To become brighter and more pleasant. Used especially of the weather: We can go to the beach if the weather clears up.