pho·​to·​chem·​i·​cal | \ ˌfō-tō-ˈke-mi-kəl How to pronounce photochemical (audio) \

Definition of photochemical

1 : of, relating to, or resulting from the chemical action of radiant energy and especially light photochemical smog
2 : of or relating to photochemistry photochemical studies

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Other Words from photochemical

photochemically \ ˌfō-​tō-​ˈke-​mi-​k(ə-​)lē How to pronounce photochemically (audio) \ adverb

Examples of photochemical in a Sentence

Recent Examples on the Web That's because hotter weather speeds up the photochemical reactions that turn pollutants from vehicle tailpipes and other sources into ozone, the invisible, lung-damaging gas in summer smog. Susanne Rust And Tony Barboza Los Angeles Times, Star Tribune, "How climate change is fueling record-breaking California wildfires, heat and smog," 13 Sep. 2020 But these materials also present a challenge for conservationists, since the materials tend to undergo color changes and structural damage due to photochemical reactions. Jennifer Ouellette, Ars Technica, "X-rays reveal the key to preserving Edvard Munch’s The Scream," 21 May 2020 In addition to methane, trees can emit what are known as volatile organic compounds, which are themselves not greenhouse gases, but can interact with other gases in the atmosphere to cause ozone and photochemical smog. Denise Chow, NBC News, "Tree-planting campaigns are gaining momentum, but climate researchers warn they're not a silver bullet," 11 Nov. 2019 The light produced as these meteors streak into our atmosphere at over 130,000 miles a second, way faster than a bullet out of a gun, is due to photochemical reactions. Mike Lynch, Twin Cities, "Sky Watch: Don’t wait for its peak to look for the Perseid meteor shower," 11 Aug. 2019 Some methane comes from photochemical reactions in their foliage. Fred Pearce, WIRED, "Trees Emit a Surprisingly Large Amount of Methane," 9 July 2019 He co-produced, and appeared in, the 2012 documentary Side By Side, an exploration of the differences between traditional photochemical filmmaking and digital processes. Time, "Why It Took Keanu Reeves 30 Years to Become an Overnight Sensation," 21 June 2019 By the end of the 1700s, scientists had realized that silver chloride and silver nitrate would darken when exposed to light, a photochemical effect that would soon make photography possible. Jennifer Ouellette, Ars Technica, "Scientists found these old photographs contain metallic nanoparticles," 12 June 2019 By comparison, our standard contact printers for photochemical preservation run at 80 frames per second (fps). Chuck Thompson, Popular Mechanics, "How Archivists Saved Damaged WWII Film for 'The Cold Blue'," 23 May 2019

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

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First Known Use of photochemical

1857, in the meaning defined at sense 1

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Time Traveler for photochemical

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The first known use of photochemical was in 1857

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Statistics for photochemical

Last Updated

28 Sep 2020

Cite this Entry

“Photochemical.” Dictionary, Merriam-Webster, Accessed 27 Oct. 2020.

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More Definitions for photochemical


pho·​to·​chem·​i·​cal | \ ˌfōt-ō-ˈkem-i-kəl How to pronounce photochemical (audio) \

Medical Definition of photochemical

1 : of, relating to, or resulting from the chemical action of radiant energy and especially light photochemical smog
2 : of or relating to photochemistry photochemical studies

Other Words from photochemical

photochemically \ -​k(ə-​)lē How to pronounce photochemically (audio) \ adverb

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