pneumococcal vaccine

[nōō′mə-kŏkəl]
n.
  1. A vaccine containing purified capsular polysaccharide antigen from the most common infectious types of Streptococcus pneumoniae, used to immunize against pneumonococcal disease.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.