Living will

A living will, also called will to live, is one type of advance health directive, or advance health care directive. It is often accompanied by a specific type of power of attorney or health care proxy. These are legal instruments that are usually witnessed or notarized. A living will usually covers specific directives as to the course of treatment that is to be taken by caregivers, or, in particular, in some cases forbidding treatment and sometimes also food and water, should the principal be unable to give informed consent ("individual health care instruction") due to incapacity.A power of attorney for health care appoints an individual (a proxy) to direct health care decisions should the principal be unable to do so.
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Noun
1. a document written by someone still legally capable requesting that they should be allowed to die if subsequently severely disabled or suffering terminal illness; "after he discovered he had AIDS he drew up a living will"
(hypernym) legal document, legal instrument, official document, instrument
(classification) law, jurisprudence

A living will is one form of advance medical directive. Advance medical directives preserve the person’s right to accept or reject a course of medical treatment even after that person becomes mentally or physically incapacitated to the point of being unable to communicate those wishes. There are two basic types of advance directives: (1) a living will, in which the person outlines specific treatment guidelines that are to be followed by health care providers; (2) a health care proxy (also called a power of attorney for health-care decision-making) in which the person designates a trusted individual to make medical decisions in the event that he or she becomes too incapacitated to make such decisions. Advance directive requirements vary greatly from one jurisdiction to another and should therefore be drawn up in consultation with an attorney who is familiar with the laws of the particular jurisdiction. (This entry is based upon material from the National MS Society).

A document that sets out guidelines for dealing with life-sustaining medical procedures in the eventuality of the signatory's sudden debilitation. - (read more on Living will)