Depression may refer to:
- Depression (mood), an increasingly common term for a sad or low mood or the loss of pleasure during which time an individual remains capable of performing personal and vocational obligations in a generally satisfactory manner
- Clinical depression, or major depressive disorder, a state of intense sadness, melancholia or despair that has advanced to the point of being disruptive to an individual's social functioning and/or activities of daily living
- Psychotic depression
- Depressive Disorder Not Otherwise Specified
- Refractory depression - depression not responding to typical modes of treatment
- Depression (physiology), a lowering, in particular a reduction in a particular biological variable or the function of an organ, contrasted to elevation
- Depression (kinesiology), an anatomical term of motion