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Pronunciation: ra'de-a'shun


  1. The act or condition of diverging in all directions from a center.
  2. The sending forth of light, short radio waves, ultraviolet rays or x-rays, or any other rays for treatment, diagnosis, or another purpose.
  3. A ray.
  4. Radiant energy or a radiant beam.

Synonym(s): radiatio

[L. radiatio, fr. radius, ray, beam]

Further information

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© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.