1. Noun.  The shooting forth of anything from a point or surface, like the diverging rays of light; as, the radiation of heat..
  2. Noun.  The process of radiating waves or particles.
  3. Noun.  The transfer of energy via radiation (as opposed to convection or conduction).
  4. Noun.  Radioactive energy.

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This entry was last updated on RefTopia from its source on 3/20/2012.