noun, plural cal·dar·i·a [kal-dair-ee-uh] /kælˈdɛər i ə/.
Origin of caldarium
Examples from the Web for caldarium
Historical Examples of caldarium
A doorway led from the tepidarium into the caldarium, or vapor-bath.Museum of Antiquity
L. W. Yaggy
Doors led into the Laconicum from both the tepidarium and the caldarium.
The tepidarium, as well as the caldarium, had a hollow floor and walls.
The cold bath, in distinction from the caldarium, the hot bath.Quintus Claudius, Volume 2 of 2
Coming from these two sources the caldarium must have been, indeed, impure.De Re Metallica