The ABO blood group system is an essential factor in blood transfusions and organ transplants. But what if there were alternative terms to describe this system? Synonyms for the ABO blood group systems could include "ABO antigen system" or "ABO typing system". These terms highlight the presence of antigens on red blood cells and the process of categorizing blood types based on these antigens. Additionally, the ABO blood group systems can also be referred to as "ABO blood group classification" or simply "ABO grouping". These synonyms help convey the significance and complexity of this vital blood classification system in healthcare and medical research.