Ito's nevus

tōz′]
n.
  1. Pigmentation of the skin that is innervated by lateral branches of the supraclavicular nerve and by the lateral cutaneous nerve of the arm, caused by the presence of scattered melanocytes in the dermis.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.