gravely disabled

a condition in which a person, as a result of a mental disorder: (a) [i]s in danger of serious physical harm resulting from a failure to provide for his essential human needs of health or safety, or (b) manifests severe deterioration in routine functioning evidenced by repeated and escalating loss of cognitive or volitional control over his or her actions and is not receiving such care as is essential for his or her health or safety.

Defined by the Supreme Court in Washington v. Harper, 494 U.S. 210 (1990).