Main Entry: smog

Pronunciation: \ˈsmäg, ˈsmȯg\

Function: noun

Etymology: smoke + fog

Date: 1884

: 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 especially from automobile exhaust

— smog·less \ˈsmä-gləs, ˈsmȯ-\ adjective