光化學煙霧 guānghuàxuéyānwù photochemical smog Origin Definitions Defs Strokes Stroke Words Sentences Sents 光化学 光化學 guānghuàxué photochemistry the branch of chemistry concerned with the chemical effects of light; also known as actinology烟雾 煙霧 yānwù noun smoke smoke or smog produced by combustion or industrial processes