To clear up is to tidy — or, of weather, to improve. Two senses that both mean something obstructive is going.
The tidying sense is the everyday one, and clearing up after a meal is a shared duty in most households. It splits round an object. The weather sense is intransitive and hopeful, since a morning that clears up has stopped raining. There are two more: clearing up a misunderstanding means resolving it, and an infection clears up when it goes.
Practised in Phrasal Verbs, A Man Called Ove
First appears in chapter 6 of A Man Called Ove.
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