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Porter's sign

[pôr′tərz]
n.
  1. An indication of aneurysm of the aortic arch marked by pulsation of the trachea when the cricoid cartilage of the larynx is drawn upward with the thumb and forefinger while the individual sits with the head thrown back and mouth closed.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.