A monotypic genus of the family Araceae comprising the water lettuce, Pistia stratiotes, a pantropical aquatic plant which forms a floating rosette of leaves and has become a troublesome weed of waterways (also called tropical duckweed, river lettuce); (also pistia) a plant of this genus, water lettuce.
Valid publication of the genus name: Linnaeus Species Plantarum (1753) II. 963.
Mid 18th century; earliest use found in New & Complete Dictionary Arts & Science. From scientific Latin Pistia (LinnaeusGenera Plantarum 275) from ancient Greek πιστός drinkable, liquid (from the base of πίνειν to drink + inserted -σ- + -τός, suffix forming verbal adjectives) + scientific Latin -ia, perhaps so called on account of its deriving its nutrients from water.