Wiktionary
vb. (context intransitive English) To become cloudy or overcast.
WordNet
Usage examples of "cloud over".
We disguised our certain expectation of the event from you, lest it should throw a cloud over the cheerful reception which was your due.
Rivers had started at the first of those musical accents, as if a thunderbolt had split a cloud over his head, he stood yet, at the close of the sentence, in the same attitude in which the speaker had surprised him—.
If the forest were cut down, then there would be no cloud over Kulal, no rain, just wind erosion, the sort of thing that's happened at Marsabit, at Meru and the Aberdares, all over the country.
A gust of the usual steady morning breeze moved the gas cloud over the devastation onto the Muslim lines, and less machine gun fire struck at them.
Her hair is woven like a cloud over the silver tricorn Night Moon Crown in the Primal Daybreak, and then allowed to flow freely down her back like an ebony waterfall.