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definitions

periarterial plexus

[pĕr′ē-är-tîr′ē-əl]
n.
  1. An autonomic plexus that accompanies an artery.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.