The Collaborative International Dictionary of English v.0.48:

Hydrophobic \Hy`dro*phob"ic\, a. [L. hydrophobicus, Gr. ?: cf.
   F. hydrophobique.]
   Of or pertaining to hydrophobia; producing or caused by
   rabies; as, hydrophobic symptoms; the hydrophobic poison.
   [1913 Webster]

WordNet (r) 3.0 (2006):

hydrophobic
    adj 1: lacking affinity for water; tending to repel and not
           absorb water; tending not to dissolve in or mix with or
           be wetted by water [ant: hydrophilic]
    2: abnormally afraid of water [syn: hydrophobic, aquaphobic]