Water-Lily, a general name applied to all members of the family Nymphceaceæ. They are aquatic herbs, native to all temperate and tropical regions. The stems are submerged, and the broad leaf-blades (lily-pads), on long petioles, float on the surface of the water. The true water-lilies are a species of Nymphæa or Castalia, the flowers being showy and of various colors. In the common species the petals are numerous and beautifully white and fragrant. The yellow pond-lily or spatter-dock is a species of Nuphar.