The story
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: Inflammation of many serosae (serous membranes), throughout the body, as a component of a systemic disease process, such as Kawasaki disease, MIS-C, or MIS-A (Multisystem Inflammatory Syndrome in Adults); thus, vasculitides, polyarthritides, and pericarditis are involved. Full definition →