Term: hematocrit or packed cell volume (PCV)
κριτής<judge > κρίνω (verb) / (=judge, separate, decide, accuse)à to separate the blood.
Hematocrit originally was used to describe the procedure used to separate blood into packed erythrocytes(PCV), buffy coat layer and plasma. Today the term hematocrit is synonymous to major blood component PCV. When a small capillary tube used to separate blood components it became microhematocrit.
The percentage of blood volume that is occupied by red blood cells to the volume of whole blood in a sample of capillary, venous, or arterial blood.