What is an MCV blood test? MCV stands for mean corpuscular volume. MCV is a measurement of the average size of your red blood cells. Lab Test: MCV, Mean Corpuscular Volume Level · This test is routinely performed as part of an automated complete blood cell count. Mean corpuscular volume (MCV) laboratory test, as part of a standard complete blood count (CBC), is used along with other RBC indices (MCH. The average size of the cells is mean corpuscular volume (MCV). The mean corpuscular volume, or mean cell volume, is a measure of the average volume of a red blood corpuscle.