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c.1600, from Late Latin rheumatismus, from Greek rheumatismos, from rheumatizein "suffer from the flux," from rheuma "a discharge from the body" (see rheum). "The meaning of a disease of the joints is first recorded in 1688, because rheumatism was thought to be caused by an excessive flow of rheum into a joint thereby stretching ligaments" [Barnhart].
rheumatism rheu·ma·tism (rōō'mə-tĭz'əm)
Any of several pathological conditions of the muscles, tendons, joints, bones, or nerves, characterized by discomfort and disability.
any of several disorders that have in common inflammation of the connective tissues, especially the muscles, joints, and associated structures. The most common symptoms are pain and stiffness. Specific diseases that are alternatively called rheumatism include rheumatoid arthritis (q.v.); rheumatic fever (q.v.); septic arthritis (q.v.) that accompanies such diseases as gonorrhea, tuberculosis, or mycotic diseases (caused by fungus); and osteoarthritis (q.v.).