A sick person can be referred to as a CASE, LEPER, INVALID, or PATIENT. A CASE is a four letter term used to describe a person who is ill or injured and in need of medical attention. A LEPER is a five letter term used to describe someone suffering from leprosy, a chronic infectious disease that affects the skin, mucous membranes, and nerves. An INVALID is a seven letter term used to describe someone who is disabled or incapacitated due to illness or injury. Lastly, a PATIENT is a seven letter term used to describe someone who is receiving medical care or treatment.