Dear Fiberbabe: I used to work in a TB san.

"Sanitorium" comes from the Latin word "sanare", which means to cure or heal. It took on its special meaning as a place for the treatment of invalids, particularly consumptives, in the late 1800s.

"Sanitarium" comes from the Latin word "sanitas", which means health. Its most common meaning is "health resort." Because of its close etymologic link with the word for "sanity", sanitarium is most easily remembered as the designation for institutions designed to treat mental disorders.