Ulva

from WordNet (r) 3.0 (2006)

Ulva
    n 1: type genus of the family Ulvaceae; green seaweed having a
         thallus two cells thick: sea lettuce [syn: {Ulva}, {genus
         Ulva}]

from The Collaborative International Dictionary of English v.0.48

Ulva \Ul"va\, prop. n. [L., sedge.] (Bot.)
   A genus of thin papery bright green seaweeds including the
   kinds called {sea lettuce}.
   [1913 Webster]

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