target cell, 1. an abnormal red blood cell characterized by a densely stained center surrounded by a pale, unstained ring circled by a dark, irregular band. Target cells occur in the blood after splenectomy, in anemia, in hemoglobin C disease, and in thalassemia. Also called leptocyte. Compare discocyte, spherocyte. 2. any cell having a specific receptor that reacts with a specific hormone, antigen, antibody, antibiotic, sensitized T cell, or other substance.
