Pistia stratiotes

from WordNet (r) 3.0 (2006)

Pistia stratiotes
    n 1: pantropical floating plant forming a rosette of wedge-
         shaped leaves; a widespread weed in rivers and lakes [syn:
         {pistia}, {water lettuce}, {water cabbage}, {Pistia
         stratiotes}, {Pistia stratoites}]

from The Collaborative International Dictionary of English v.0.48

Water lettuce \Wa"ter let"tuce\ (Bot.)
   A plant ({Pistia stratiotes}) which floats on tropical
   waters, and forms a rosette of spongy, wedge-shaped leaves.
   --J. Smith (Dict. Econ. Plants).
   [1913 Webster]

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