The Collaborative International Dictionary of English v.0.48:
Sudatorium \Su`da*to"ri*um\, n.; pl. Sudatoria. [L.] A sudatory. --Dunglison. [1913 Webster]WordNet (r) 3.0 (2006):
sudatorium n 1: a bathhouse for hot air baths or steam baths [syn: sudatorium, sudatory]