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photochemical smog

noun, Meteorology
air pollution containing ozone and other reactive chemical compounds formed by the action of sunlight on nitrogen oxides and hydrocarbons, especially those in automobile exhaust.
Also called oxidant smog, smog.
Origin of photochemical smog
1957; photo- + chemical Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for photochemical smog
  • The dark region over the sunlit pole is believed to be a high layer of photochemical smog.
  • The kinetics and mechanisms of the homogeneous elementary reactions involved in photochemical smog formation were investigated.
photochemical smog in Medicine

photochemical smog n.
Air pollution produced by the action of sunlight on hydrocarbons, nitrogen oxides, and other pollutants.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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photochemical smog in Science
photochemical smog
See smog.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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