SINCE 1828

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acid fog

noun

Definition of acid fog

:fog having increased acidity caused by environmental factors (such as atmospheric pollutants)

Even so, a combination of acid fog and ozone may have made trees on this and other Eastern summits more vulnerable to bugs, weather, and drought.
—Edmund Faltermayer, Fortune, 17 July 1989

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First Known Use of acid fog

1878

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