Available Definitions:
1) n. - A water nymph; one of the lower female divinities, fabled to preside over some body of fresh water, as a lake, river, brook, or fountain.
2) n. - Any species of a tribe (Naiades) of freshwater bivalves, including Unio, Anodonta, and numerous allied genera; a river mussel.
3) n. - One of a group of butterflies. See Nymph .
4) n. - Any plant of the order Naiadaceae, such as eelgrass, pondweed, etc.