Meaning of blood group

blood' group"

Pronunciation: [key]
— Med. Med.
  1. any of various classes into which human blood can be divided according to immunological compatibility, based on the presence or absence of specific antigens on red blood cells. Also calledCf. ABO system, Rh factor.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.