Air pollution characterized by a hazy and often highly irritating atmosphere resulting from a mixture of fog with smoke and other air pollutants. [smoke + fog]
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smog 'smägalso 'smȯg n a fog made heavier and darker by smoke and chemical fumes also a photochemical haze caused by the action of solar ultraviolet radiation on atmosphere polluted with hydrocarbons and oxides of nitrogen esp. from automobile exhaust
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(smog) a mixture of smoke and fog; a colloid system in which the disperse phase consists of a mixture of gas and moisture and the dispersion medium is air.Medical dictionary. 2011.