Thermae

In ancient Rome, thermae (from Greek θερμός thermos, "hot") and balneae (from Greek βαλανεῖον balaneion) were facilities for bathing. Thermae usually refers to the large imperial bath complexes, while balneae were smaller-scale facilities, public or private, that existed in great numbers throughout Rome.

Most Roman cities had at least one, if not many, such buildings, which were centres not only for bathing, but socializing. Roman bath-houses were also provided for private villas, town houses, and forts. They were supplied with water from an adjacent river or stream, or more normally, by an aqueduct. The water would be heated by a log fire before being channelled into the hot bathing rooms. The design of baths is discussed by Vitruvius in De Architectura.

Thermae, balneae, balineae, balneum and balineum may all be translated as "bath" or "baths", though Latin sources distinguish among these terms.

Balneum or balineum, derived from the Greek βαλανεῖον signifies, in its primary sense, a bath or bathing-vessel, such as most persons of any consequence amongst the Romans possessed in their own houses, and hence the chamber which contained the bath, which is also the proper translation of the word balnearium. The diminutive balneolum is adopted by Seneca to designate the bathroom of Scipio, in the villa at Liternum, and is expressly used to characterise the modesty of republican manners as compared with the luxury of his own times. But when the baths of private individuals became more sumptuous, and comprised many rooms, instead of the one small chamber described by Seneca, the plural balnea or balinea was adopted, which still, in correct language, had reference only to the baths of private persons. Thus Cicero terms the baths at the villa of his brother Quintusbalnearia. Balneae and balineae, which according to Varro have no singular number, were the public baths. But this accuracy of diction is neglected by many of the subsequent writers, and particularly by the poets, amongst whom balnea is not uncommonly used in the plural number to signify the public baths, since the word balneae could not be introduced in a hexameter verse. Pliny also, in the same sentence, makes use of the neuter plural balnea for public, and of balneum for a private bath.

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