photolysis
noun
pho·tol·y·sis fō-ˈtä-lə-səs 
: chemical decomposition by the action of radiant energy (such as light)
photolytic
ˌfō-tə-ˈli-tik
adjective photolytically
ˌfō-tə-ˈli-ti-k(ə-)lē
adverb 
Example Sentences
Recent Examples on the Web 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
Davide Castelvecchi, Scientific American, 16 Dec. 2010 Word History
Etymology
New Latin
First Known Use
1903, in the meaning defined above
Medical Definition
photolysis
noun
pho·tol·y·sis fō-ˈtäl-ə-səs
plural photolyses -ˌsēz
: chemical decomposition by the action of radiant energy compare radiolysis