A clinical disorder that can produce disruptive and profoundly deep and recurring feelings of sadness, negativity, irritability, and hopelessness
Clinical depression is usually understood as a mood disorder marked by progressively heightened levels of irritability, anxiety, and feelings of worthlessness. Manic depression is closely associated with bipolar disorder with manifesting episodes of mania. Under the current Diagnostic Statistical Manual (DSM) the clinical term for manic depression has been replaced by bipolar disorder.