Disorder

Disorder may refer to randomness, a lack of intelligible pattern, or:

Healthcare

Disorder (medicine), a functional abnormality or disturbance
Mental disorder or psychological disorder, a psychological pattern associated with distress or disability that occurs in a person and is not a part of normal development or culture:

Anxiety disorder, different forms of abnormal and pathological fear and anxiety
Conversion disorder, neurological symptoms such as numbness, blindness, paralysis, or fits, where no neurological explanation is possible
Obsessive–compulsive disorder, an anxiety disorder characterized by repetitive behaviors aimed at reducing anxiety
Obsessive–compulsive personality disorder, obsession with perfection, rules, and organization
Personality disorder, an enduring pattern of inner experience and behavior that deviates markedly from the expectations of the culture of the person who exhibits it