A general term used to refer to any departure from health in which a patient suffers. It can be defined as disorder of bodily function or destructive processes in organs, organs' systems or in an organism with recognisable signs and symptoms, and in many cases a known cause. The words disease , illness and sickness are used often interchangeably but are not synonymous. Rather, whereas disease relates to a physiological or psychological dysfunction, an illness is the subjective state of a patient who feels unwell and sickness encompasses a state of social dysfunction, such as the role that the individual assumes when ill.