smog

noun \ ˈsmäg , ˈsmȯg \

Definition of smog

: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

Recent Examples of smog from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'smog.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of smog

smoke + fog

smog Synonyms

Synonyms
brume, fog, gauze, mist, murk, reek, haze, soup
Related Words
bank, cloud, fume, miasma, smoke, smother, steam

Other Climate/Meteorology Terms


SMOG Defined for English Language Learners

smog

noun

Definition of smog for English Language Learners

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


SMOG Defined for Kids

smog

noun \ ˈsmäg \

Definition of smog for Students

: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

noun \ ˈsmäg also ˈsmȯg \

medical Definition of smog

: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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