What does the medical abbreviation RDW mean?

Answer 1

Red Cell Distribution Width
RDW = Red cell Distribution Width. A measure in variation of the sizes of the Erythocytes (red blood cells)
RDW stands for red cell distribution width. It is a measure of the variability of the size (volume) of red cells. Red cells of uniform size--no matter what that size is--will have a low RDW. A population of cells which vary greatly in size will have a high RDW. Another name for variability in red cell size is anisocytosis. In both thallasemia and iron deficiency anemia, the average cell size (measured as MCV, mean corpuscular volume) is low. But in iron deficiency anemia, unlike thallasemia, the RDW is increased.
Red Cell Distribution Width in Percentage
Red-Blood Cell Distribution Width