rubella HI test

n.
  1. A hemagglutination inhibition test for rubella in which the presence of hemagglutination inhibition titer in the absence of disease indicates previous infection and therefore immunity to reinfection.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.