Definition of Reticulocyte

Reticulocyte: A young red blood cell that usually remains in the bone marrow with only a few venturing out into the circulating blood. The number of reticulocytes in blood rises when red cell production is unusually vigorous, as after a major bleeding episode or after the bone marrow has been suppressed and is regenerating, or when there is unusually rapid red blood cell destruction as in cases of hemolytic anemia. The reticulocyte is so named because it has a fine reticulum representing ribosomal remains.