[gamma globulin] n (1937) 1 a: a protein fraction of blood rich in antibodies b: a sterile solution of gamma globulin from pooled human blood administered esp. for passive immunity against measles, German measles, infectious hepatitis, or poliomyelitis
2: any of numerous globulins of blood plasma or serum that have less electrophoretic mobility at alkaline pH than serum albumins, alpha globulins, or beta globulins and that include most antibodies--compare antibody