"Autologous" refers to something that originates from the same individual. In medical contexts, it often describes procedures or treatments that use a person's own cells, tissues, or organs. For example, in an autologous blood transfusion, a patient donates their own blood before surgery, which is then returned to them during or after the procedure. This approach is commonly used in various therapies, such as autologous stem cell transplantation, where a patient's own stem cells are collected, treated, and reintroduced to help combat diseases like cancer. Using autologous materials can reduce the risk of rejection and complications associated with donor tissues.