transfusion Syllabification: (trans·fu·sion)Pronunciation: /transˈfyo͞oZHən/Translate transfusion | into French | into German | into Italian | into Spanish Definition of transfusion noun an act of transfusing donated blood, blood products, or other fluid into the circulatory system of a person or animal. transfusion in other Oxford dictionaries Definition of transfusion in the British & World English dictionary