phantom limb 
noun
A sensation experienced by someone who has had a limb amputated that the limb is still there: [as modifier]: phantom limb pain...
- Phantom limb pain, stump pain and phantom limb sensation describe the feelings of people who are missing a limb or part of a limb.
- If in addition central pain processes are active, phantom pain is experienced in the phantom limb.
- Soon after amputation, many amputees feel the presence of a phantom limb or a feel that there is a limb where there isn't.