Balneary \Bal”ne*a*ry\, n. [L. balnearium, fr. balneum bath.]
A bathing room. –Sir T. Browne.
balneal or balneary (ˈbælnɪəl, ˈbælnɪərɪ)
rare of or relating to baths or bathing
[C17: from Latin balneum bath, from Greek balaneion ]
without difficulty we opened the door of the balneary, next to the infirmary.
Separated one from the other by thick curtains were some tubs, I don’t recall how many. The monks used them for their ablutions, on the days the Rule established, and Severinus used them for therapeutic reasons, because nothing can restore body and mind better than a bath. A fireplace in one corner allowed the water to be heated easily. We found it dirty with fresh ashes, and before it a great cauldron lay, overturned. The water could be drawn from a font in another corner.
Source: The Name of the Rose by Umberto Eco.