Externalizing disorders are mental disorders characterized by externalizing behaviors, maladaptive behaviors directed toward an individual’s environment, which cause impairment or interference in life functioning. In contrast to individuals with internalizing disorders who internalize (keep inside) their maladaptive emotions and cognitions, such feelings and thoughts are externalized (manifested outside) in behavior in individuals with externalizing disorders. Externalizing disorders are often specifically referred to as disruptive behavior disorders (attention-deficit/hyperactivity disorder, oppositional defiant disorder, and conduct disorder) or conduct problems which occur in childhood. Externalizing disorders, however, are also manifested in adulthood.
For example, alcohol- and substance-related disorders and antisocial personality disorder are adult externalizing disorders.Externalizing psychopathology is associated with antisocial behavior, which is different from and often confused for asociality.
Courtesy : wikipedia