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Medical Term:


Pronunciation: rar'e-fak'shun


  1. The process of becoming light or less dense; the condition of being light; opposed to condensation.
  2. In vascular physiology, the process that results in a reduction in the density of capillaries in a tissue.

[L. rarus, thin, scanty + facio, to make]

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