photodecomposition

noun

pho·​to·​de·​com·​po·​si·​tion ˌfō-tō-ˌdē-ˌkäm-pə-ˈzi-shən How to pronounce photodecomposition (audio)
: photolysis

Word History

First Known Use

1889, in the meaning defined above

Time Traveler
The first known use of photodecomposition was in 1889

Rhymes for photodecomposition

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Browse Nearby Words

photocurrent
photodecomposition
photodegradable
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Cite this Entry

“Photodecomposition.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/photodecomposition. Accessed 7 Jul. 2026.

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Medical Definition

photodecomposition

noun
pho·​to·​de·​com·​po·​si·​tion -ˌdē-ˌkäm-pə-ˈzish-ən How to pronounce photodecomposition (audio)
: chemical breaking down (as of a pesticide) by means of radiant energy
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