photochemistry

noun

pho·​to·​chem·​is·​try ˌfō-tō-ˈke-mə-strē 

1

: a branch of chemistry that deals with the effect of radiant energy in producing chemical changes

2

a

: photochemical properties

the photochemistry of gases

b

: photochemical processes

photochemistry of vision

photochemist

ˌfō-tō-ˈke-mist 

noun

Examples of photochemistry in a Sentence

Recent Examples on the Web

Both hazes result from the photochemistry of solar extreme ultraviolet light reacting with molecules such as nitrogen and methane. —Keith Cooper, Space.com, 12 June 2025

Astronomers believe this breakdown leads to complex photochemistry in Titan’s atmosphere, where the products react with each other and with nitrogen. —The Physics Arxiv Blog, Discover Magazine, 15 Jan. 2024

The planet is so hot, the processes that normally lead to the creation of sulfur dioxide shouldn’t be happening—which means that less common reactions, like photochemistry, are likely responsible. —Dan Falk, Smithsonian Magazine, 5 July 2023

Word History

First Known Use

1860, in the meaning defined at sense 1

Rhymes for photochemistry

• biochemistry
• cytochemistry
• geochemistry
• histochemistry
• neurochemistry
• phytochemistry
• thermochemistry
• biogeochemistry
• chemistry
• electrochemistry
• immunochemistry
• radiochemistry

Medical Definition

photochemistry

noun

pho·​to·​chem·​is·​try -ˈkem-ə-strē 

plural photochemistries

1

: a branch of chemistry that deals with the effect of radiant energy in producing chemical changes

2

a

: photochemical properties

the photochemistry of gases

b

: photochemical processes

the photochemistry of vision