Skip to Content
Medical Term:


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]

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.