hydrophobia UK /ˌhaɪ.dɹə(ʊ)ˈfəʊ.bi.ə/US /ˌhaɪ.dɹəˈfoʊ.bi.ə/ noun3 •An aversion to water, as a symptom of rabies; the disease of rabies itself.Now that I have breathed a little, I am anxious to know your opinion of the nature of that affection in the throat, which deprives a patient of the power of swallowing in consequence of hydrophobia. — 1796 •(informal) A morbid fear of water; aquaphobia. •A lack of affinity for water; the quality of being hydrophobic formshydrophobias