What is the definition or description of: mood disorders?

Disturbed Mood: Mood disorders are defined as a disturbed mood such that the disturbance causes impairment in social, work, or other important areas of life functioning. Examples of mood disorders include: major depressive disorder, bipolar disorder, postpartum depression, substance-induced depression, mood disorder due to a general medical condition, and there are others. Fortunately treatment is available.

Mood disorders: Disturbance in moods affecting daily functioning or causing significant distress. Can be bipolar do, major depression, dysthymia, cyclothymia, or organic mood disorders.