Rheumatism or rheumatic disorder is an umbrella term for conditions causing chronic, often intermittent pain affecting the joints and/or connective tissue. The study of, and therapeutic interventions in, such disorders is called rheumatology.The term “rheumatism”, however, does not designate any specific disorder, but covers at least 200 different conditions. Sources dealing with rheumatism tend to focus on arthritis,[citation needed] but “rheumatism” may also refer to other conditions causing chronic pain, grouped as “non-articular rheumatism”, also known as “regional pain syndrome” or “soft tissue rheumatism”.The term “Rheumatic Diseases” is used in MeSH to refer to connective tissue disorders. The term “rheumatism”, to the inclusion of arthritis, covers at least 200[citation needed] different conditions.

The term rheumatism in the current sense has been in use since the late 17th century, as it was believed that chronic joint pain was caused by excessive flow of rheum or bodily fluids into a joint. The term rheumatism is somewhat older, adopted in the early 17th century in a different meaning, from from Late Latin rheumatismus, ultimately from Greek ῥευματίζομαι “to suffer from a flux”, i.e. any discharge of blood or bodily fluid (Mark 5:25 uses ῥύσις, from the same root, for “flow of (menstrual) blood”, translated as “flux” in KJV). Before the 17th century, joint pain thought to be caused by viscous humours seeping into the joints was named gout, a word adopted in Middle English from Old French gote “a drop; the gout, rheumatism”.