Depression What is Depression? The dictionary's definition of depression is: a lowering or decrease of functional activity; a mental state depressed mood characterized by discouragement, sadness, and despair. Often decisions range form normal feelings of the blues thought to major depression. A significant increase or decrease in appetite and time spent sleeping, feelings of dejection and hopelessness, and sometimes suicidal tendencies. Depression is a disorder characterized by feelings of inadequacy, error, sadness, helpless, and gloom. Depression is an illness with a wide range of physical and mental symptoms, which somet