1. An infection of hair shafts, especially of the axillary and pubic regions, with microorganisms of the genus Nocardia. Yellow, red, or black concretions develop around the infected hair shafts.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.