photolysis

1 of 2

noun

pho·​tol·​y·​sis fō-ˈtä-lə-səs How to pronounce photolysis (audio)
: chemical decomposition by the action of radiant energy (such as light)
photolytic adjective
photolytically adverb

photolytic

2 of 2

adjective

pho·​to·​lyt·​ic ¦fōtᵊl¦itik How to pronounce photolytic (audio)
: of, relating to, or formed by photolysis
photolytically adverb

Examples of photolysis in a Sentence

Recent Examples on the Web
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Noun
Flash photolysis is still used to study semiconductors, nanoparticles, and photosynthesis, among other things. IEEE Spectrum, 18 Feb. 2022 But sunlight in the upper atmosphere is continuously breaking down the gas by photolysis, so some process must be slowly replacing it. Davide Castelvecchi, Scientific American, 16 Dec. 2010

Word History

Etymology

Noun

New Latin

Adjective

phot- + -lytic

First Known Use

Noun

1903, in the meaning defined above

Time Traveler
The first known use of photolysis was in 1903

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Cite this Entry

“Photolysis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/photolysis. Accessed 27 Jun. 2026.

Medical Definition

photolysis

noun
pho·​tol·​y·​sis fō-ˈtäl-ə-səs How to pronounce photolysis (audio)
plural photolyses -ˌsēz How to pronounce photolysis (audio)
: chemical decomposition by the action of radiant energy compare radiolysis
photolytic adjective
photolytically adverb

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