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smog

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noun \ˈsmäg, ˈsmȯg\

Simple Definition of smog

  • : fog mixed with smoke : a cloud of dirty air from cars, factories, etc., that is usually found in cities

Source: Merriam-Webster's Learner's Dictionary

Full Definition of smog

  1. :  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

smogless

play \ˈsmä-gləs, ˈsmȯ-\ adjective

Examples of smog in a sentence

  1. <the city's smog was once so bad that darkness often prevailed, even at noon>



Origin and Etymology of smog

smoke + fog


First Known Use: 1884

Other Climate/Meteorology Terms

Rhymes with smog


SMOG Defined for Kids

smog

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noun \ˈsmäg\

Definition of smog for Students

  1. :  a fog made heavier and thicker by the action of sunlight on polluted air



History for smog

The word smog was coined in England in 1905 by combining the words smoke and fog. The person who coined the word wanted to more accurately describe the atmosphere in London caused by fog mixing with smoke from coal furnaces used for heating. In the United States smog often describes any sort of visible air pollution, such as the haze around cities produced by automobile exhaust affected by sunlight.


Medical Dictionary

smog

play
noun \ˈsmäg also ˈsmȯg\

Medical Definition of smog

  1. :  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




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