Xenotransplantation, also known as cross-species transplantation, refers to the procedure of transplanting living cells, tissues or organs from one species to another. Some synonyms for xenotransplantation include xenografting, heterotransplantation, and interspecies transplantation. Xenografting involves the transfer of cells, tissues, or organs between different animal species, whereas heterotransplantation is the transplantation of tissues or organs from one individual to another of the same species but with different genetic makeup. Interspecies transplantation is a broader term that includes transplantations between plant and animal species. Though these terms have some differences in their definitions, they all refer to the concept of using living material from a different species in life-saving medical procedures.