The Free On-line Dictionary of Computing (30 December 2018):

radiosity

    A method for rendering a view of a
   three-dimensional scene that provides realistic lighting
   effects, such as interobject reflections and color bleeding.
   Radiosity methods are computationally intense, due to the use
   of linear systems of equations and the spatial complexity of
   large scenes.

   Usenet newsgroup: news:comp.graphics.

   [Is radiosity more accurate than ray tracing?  Does it take
   more computing power?  How does compute time scale with scene
   complexity?]

   (2003-06-01)