Definition: The act of a physician or other third party ending a patient's life in response to severe pain and suffering.
Voluntary Euthanasia refers to the action taken by the physician and the patient, who both agree (with informed consent) to end the patient's life.
Involuntary Euthanasia refers to a third party taking a patient's life without the informed consent of the patient. This is commonly practiced in veterinary medicine when animals are "put down" or "put to sleep." In modern medicine, it could conceivably be applied to the act of taking a terminally ill, suffering patient's life who has lost all mental capacity to make his/her own decisions.
Also Known As: physician-assisted death, physician-assisted suicide, mercy killing
