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radiant flux

American  

noun

Physics.
  1. the time rate of flow of radiant energy.


radiant flux British  

noun

  1.  Φe.  the rate of flow of energy as radiation. It is measured in watts

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of radiant flux

First recorded in 1915–20