Psychosomatic describes a physical illness that results at least in part from mental causes. If you are under a lot of stress, the strain can trigger a psychosomatic condition like a stomach ulcer.
Have you heard of the mind-body connection? That if you enjoy mental well-being you will also likely have good physical health — and vice versa? Psychosomatic originally used to describe the relationship between the body and the mind, and it comes from the merging of two Greek words, psykhe, mind, and somatikos, "body." A psychosomatic illness is triggered or made worse by a mental issue; the body gets worn down by things like constant worry and stress.