Definition from Wiktionary, the free dictionary
irradiance (plural irradiances)
- The act of irradiating; emission of rays of light.
- That which irradiates or is irradiated; lustre; splendour; brilliancy.
- (physics) The radiant power received by unit area of surface
The act of irradiating
That irradiates or is irradiated
physics: Radiant power received by unit area of surface