Definition: Regrafting is a medical procedure that involves transferring one part of an animal's body, such as its heart or lungs, to another animal. This can be done in order to replace a damaged organ or muscle, or for other reasons, like to improve the health and fitness of a sick animal. The term "regrafting" is used in veterinary medicine to describe this process because it involves transferring an organ from one part of a living animal to another without altering its genetic makeup.