Other forms: sanitariums; sanitaria
In the past, someone who was recovering from a long-term illness might stay at a sanitarium, a special kind of hospital. Many sanitariums in the U.S. once treated patients with tuberculosis.
A sanitarium was also often called a sanatorium. Even more confusingly, both words were sometimes used to mean "health resort," something closer to a spa than a hospital. Before antibiotics were invented, the most effective treatment for tuberculosis and other lung diseases was fresh air and healthy food at a sanitarium. The word is rooted in the Latin sanitas, "health."