77 Followers. A. RDW stands for the red blood cell distribution width. This is a standard reported measure on a complete blood count (CBC) lab test. It measures the variability in red blood cell size. In the normal state, red blood cells are continually being produced and removed from the blood at a steady rate.. RDW stands for the red blood cell distribution width. This is a standard reported measure on a complete blood count (CBC) lab test.