Of stormy weather, to dissipate, to become calm.(verb)
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Use "clear up" in a sentence
"Worst-case scenario, she said, Brie would be sent home with some antibiotics and her cough would clear up within a few days."
"We had her see an excellent psychiatrist, Dr. Robert Samuels, and she was given some new medication that seemed to clear up the delusions."
"Before leaving this point, we should clear up an area of misunderstanding about lean supply—the frequent assumption in the West that all parts are “sole-sourced” in a lean-supply system—that is, every part is supplied by only one supplier."