Blumberg's sign

[blŭmbərgz, blōōm-]
n.
  1. An indication of peritonitis in which pain is felt upon sudden release of steadily applied pressure on a suspected area of the abdomen.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.