Autoinoculation is derived from the Latin root words "autos" and "inoculate" that mean "self implanting" or "self infection" or "implanting something from oneself". Autoinoculation can refer to both beneficial medical procedures (e.g. vaccination) as well as non-beneficial or harmful natural processes (e.g. infection or disease). One beneficial autoinoculation medical procedure is when cells are removed from a person's body, medically altered then reinserted ("implanted" or "infected") into the same organism or person again to achieve some diagnostic or treatment aim.