Skip to Content


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]

Disclaimer: This site is designed to offer information for general educational purposes only. The health information furnished on this site and the interactive responses are not intended to be professional advice and are not intended to replace personal consultation with a qualified physician, pharmacist, or other healthcare professional. You must always seek the advice of a professional for questions related to a disease, disease symptoms, and appropriate therapeutic treatments.
© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.