differential blood count

[dĭf′ə-rĕnshəl]
n.
  1. An estimate, based on cell counts in a representative sample, of the percentage of white blood cell types that make up the total white blood cell count.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.