[1] : The Collaborative International Dictionary of English v.0.48

waterweed \wa"terweed`\, n. bot.
   see anacharis.
   1913 webster
see also:
anacharis 

[2] : The Collaborative International Dictionary of English v.0.48

anacharis \anach"aris\, n. nl., fr. gr. 'ana` up + xa`ris
   grace. bot.
   a fresh-water weed of the frog's-bit family
   hydrocharidaceae, native to america. transferred to
   england it became an obstruction to navigation. called also
   waterweed and water thyme.
   1913 webster anachoret
see also:
hydrocharidaceae waterweed water thyme 

[3] : WordNet (r) 2.0

waterweed
     n : a weedy aquatic plant of genus elodea

Waterweed >> W Words
Waterweed, definition of term: Waterweed
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