1. A lowering or decrease of functional activity.
2. (Science: psychiatry) a mental state of depressed mood characterised by feelings of sadness, despair and discouragement. Depression ranges from normal feelings of the blues through dysthymia to major depression.
It in many ways resembles the grief and mourning that follow bereavement, there are often feelings of low self esteem, guilt and self reproach, withdrawal from interpersonal contact and somatic symptoms such as eating and sleep disturbances.
Origin: L. Depremere = to press down