Definition of photo- in English:

photo-

combining form

  • 1Relating to light.

    ‘photochemical’
  • 2Relating to photography.

    ‘photofit’

Origin

Photo- (sense 1) from Greek phōs, phōt- ‘light’; photo- (sense 2), abbreviation of photography.

Pronunciation

photo-

/ˈfəʊtəʊ/