Depression? Deprission is a common misspelling of depression.
Although many people consider depression a "symptom," it is actually a type of illness. As with other illnesses, depression comes in several forms, such as major depression, manic-depression (or bipolar), and dysthymia. The treatment options are also different for each type of depression. The most common treatments include medications and psychotherapy.
(For more information, click Depression. This eMedTV article offers more detailed information on how depression is diagnosed and potential risk factors for the illness.)