Undine \Un*dine"\, n. [G. undine, or F. ondin, ondine, from L. unda a wave, water.] One of a class of fabled female water spirits who might receive a human soul by intermarrying with a mortal. [1913 Webster]
31 Moby Thesaurus words for "undine": Davy, Davy Jones, Neptune, Nereid, Oceanid, Oceanus, Poseidon, Thetis, Triton, elemental, elemental spirit, fresh-water nymph, gnome, kelpie, limniad, man fish, mermaid, merman, naiad, nix, nixie, ocean nymph, salamander, sea nymph, sea-maid, sea-maiden, siren, sylph, water god, water spirit, water sprite