Autotomy

Broadly, autotomy means the deliberate removal or shedding of a body part. An example of autotomy in the animal world is when a lizard dislodges its tail to escape from an attack. In humans, autotomy is when a person deliberately cuts off one of their body parts. This is a form of self-harm or self-mutilation which are maladaptive behaviors. A person having a delusion who cuts off their own finger would be autotomy.