‘Brain death’ is the colloquial term for the determination of human death by showing the irreversible cessation of the clinical functions of the brain. It is an unfortunate term because it erroneously implies that there are two types of death: ordinary death and brain death. It also misleadingly implies that only the brain and not the human being is dead. In fact, the term properly refers to a method by which physicians may determine the unitary phenomenon of human death in the relatively rare situation in which ventilation (and hence circulation) are mechanically supported. Because the term ‘brain death’ is ingrained in common usage, it is essential that we understand and use it correctly. There is evidence that the term and concept of brain death are widely misunderstood by the public and by physicians (Youngner et al., 1989).

Several other terms have been used synonymously or in related contexts. The term ‘cerebral death’ should be abandoned because it adds nothing and promotes confusion. Some have used it to refer generally to brain death and others specifically to the higher brain formulation of death (discussed below) in which some scholars advocate the unaccepted idea that loss of functions of the cerebrum alone should be sufficient grounds for death. Translations of the term ‘brain death’ into other languages add to the confusion because it is morte cerébrale in French, muerte cerebrale in Spanish, and morte cerebrale in Italian.

Within the concept of brain death, scholars have argued about how much and what part of the brain must cease to function for a patient to be dead, and have coined the terms ‘whole brain death’, ‘brainstem death’, and ‘neocortical death’ discussed later (Bernat, 1992). These terms may be useful as theories of brain death but should not be used synonymously with the overall concept. The term ‘irreversible coma’, cited in the title of the Harvard Ad Hoc Committee Report (Ad Hoc Committee 1968), also adds confusion by suggesting that the brain dead patient is simply in a coma; it should be omitted in this context. The clearest statement a physician can make about a patient declared brain dead is ‘the patient was declared dead using brain death tests’.