Removal of part or all of a body part enclosed by skin. For example, removal of part of a finger or an entire finger would be termed an amputation. Removal of an appendix, on the other hand, would not be termed amputation. A person who has undergone an amputation is called an amputee.

Amputation usually takes place during surgery in a hospital operating room. It is performed to prevent the spread of gangrene as a complication of frostbite, injury, diabetes, arteriosclerosis (hardening of the arteries), or any other illness that impairs blood circulation. It is also performed to prevent the spread of bone cancer and to curtail loss of blood and infection in a person who has suffered severe, irreparable damage to a limb.

When performing an amputation, surgeons generally cut above the diseased or injured area so that a portion of healthy tissue remains to cushion bone. Sometimes the location of a cut may depend in part on its suitability to be fitted with an artificial limb, or prosthesis.  WebMD