rheumatism -- (any painful disorder of the joints or muscles or connective tissues)
rheumatoid arthritis, atrophic arthritis, rheumatism -- (a chronic autoimmune disease with inflammation of the joints and marked deformities; something (possibly a virus) triggers an attack on the synovium by the immune system, which releases cytokines that stimulate an inflammatory reaction that can lead to the destruction of all components of the joint)