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

Law enforcement
Civil disorder, one or more forms of disturbance caused by a group of people
Lawlessness, a lack of laws or law enforcement

Science
Crystallographic disorder, disordered atom locations in crystals
Order and disorder

Arts, entertainment, and media
Films
Disorder (1962 film), a film by Franco Brusati
Disorder (2009 film), a Chinese documentary
Disorder (2015 film), a French film

Music
Disorder (band), a Bristol-based hardcore punk band
Disorder (album), an album by The Gazette
Disorder (EP), an EP by Front Line Assembly
"Disorder", a song by Joy Division from the 1979 album Unknown Pleasures

Mail order
Dis-order, the mail order service of Displeased Records

See also
Chaos
Order