Entry 1 sense Webster, 1913 Hydrotherapy /hīdˌ-rōth-ĕr'-əp-ē/ · Hy·dro·ther·a·py · IPA /hˌaɪdroʊθˈɛrəpiː/ 01 n. See Hydropathy. 1. See Hydropathy.(Med.) See: Hydropathy