any mental disorder not caused by detectable organic abnormalities of the brain and in which a major disturbance of emotions is predominant

a state of clinical depression in which the person exhibits irritability and restlessness

severe and progressive depression in infants who lose their mother and do not get a suitable substitute

mild chronic depression

a state of depression for which there is no apparent precipitating cause

an inappropriate state of depression that is precipitated by events in the person's life (to be distinguished from normal grief)