actinometer Meaning, Definition & Usage

  1. noun an instrument for measuring the intensity of electromagnetic radiation (usually by the photochemical effect)

WordNet

Ac`ti*nom"e*ter noun
Etymology
Gr. , , ray + -meter
Definitions
  1. (Physics)(a) An instrument for measuring the direct heating power of the sun's rays. (b) An instrument for measuring the actinic effect of rays of light.

Webster 1913