Definition:
A syndrome is a set of signs and symptoms that are known to occur together and suggest a particular abnormality, but without a known cause. It does not imply that the condition is less severe than a disease; it means that it's not as well understood.
]Fibromyalgia and chronic fatigue syndrome both fit this definition because researchers haven't yet discovered what causes the numerous symptoms and changes in the body.
Also see: Definition of Disease
