Definition of actinic in English:



  • (of light or lighting) able to cause photochemical reactions, as in photography, through having a significant short wavelength or ultraviolet component.

    • ‘This approach can be very cost-effective, since the cost of non-LED based actinic illumination is significantly lower than LED-based illumination.’
    • ‘These states were detected both by short actinic flashes and by the switching of the actinic illumination level between different stationary state values.’
    • ‘Continuous actinic illumination was provided through the fourth port of the vessel from a Schott KL1500 light source.’
    • ‘Following this, leaves were illuminated with actinic light until a steady-state photosynthetic rate was reached.’
    • ‘Leaves were then illuminated with actinic light and saturating flashes of 0.7 s duration were applied every 1.5 min.’


Mid 19th century: from Greek aktis, aktin- ‘ray’ + -ic.