Definition of photochemical in English:



  • 1Relating to or caused by the chemical action of light.

    ‘a photochemical reaction’
    • ‘The small rings are made to move around the big ring by bathing them in light of different wavelengths; the light energy fuels the photochemical reaction to break the hydrogen bonds.’
    • ‘This is a problem for museums because photochemical oxidation is not required; the reactions take place in the dark.’
    • ‘One influential school of thought focuses on the effects of oxidation reactions brought about by active oxygen species generated by photochemical reactions involving blue and UV light.’
    • ‘Photoproduct levels may reflect the net photochemical effects of light and oxygen within tissue on native photosensitizers.’
    • ‘In addition, the carrier molecule may also protect some dyes from chemical, photochemical or radiolytic degradation.’
    1. 1.1 Relating to photochemistry.
      • ‘The program emphasized photochemical approaches, although thermochemical processes were also evaluated.’
      • ‘Ever since mechanical and photochemical advances in the 19th century gave rise to the invention of motion picture recording and display, the evolution of the ‘art’ of film has been a consequence of the rate of technological change.’