• (n.) A system of treating disease by baths and mineral waters.
Hy`dro·ther`a·peu'tics noun [ Hydro- , 1 + therapeutics .] (Medicine) A system of treating disease by baths and mineral waters. 
Type: Term Pronunciation: hī′drō-thār′ă-pyū′tiks Synonyms: hydrotherapy
hydrotherapy, hydrotherapeutics 1. Treatment of an illness with water by external application, either for its pressure effect or as a means of applying physical energy to the tissues. 2. The external application of water; such as, in warm baths to relax or with cold compresses to reduce fevers.
hydrotherapy.