Emotional state characterized by extreme sadness and dejection. A depressed mood is often temporary and should be differentiated from clinical depresion, which is a more serious and long- term illness that affects various aspects of the patient’s life.

Clinical depression can include a variety of symptoms, such as deep sadness, loss of interest in pleasurable activities, insomnia or oversleeping, irritability, and fatigue. Feelings of hopelessness, pessimism, guilt, worthlessness, and helpnessness often plague the individuals suffering from this disorder.