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signal node

[sĭg′nəl]
n.
  1. A firm, palpable, supraclavicular lymph node, usually on the left side, whose tumorous condition is usually secondary to primary carcinoma in one of the viscera.jugular gland Virchow's node
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.