define bipolar disorder
Bipolar disorder, also known as bipolar affective disorder and manic-depressive illness, is a mental disorder characterized by periods of elevated mood and periods of depression.The elevated mood is significant and is known as mania or hypomania depending on the severity or whether there is psychosis.hile in adults the course of bipolar disorder is characterized by discrete episodes of depression and mania with no clear symptomatology between them, in children and adolescents very fast mood changes or even chronic symptoms are the norm.