pond·weed /ˈpɑndˌwid/
  眼子菜
  Pond·weed n. Bot. Any aquatic plant of the genus Potamogeton, of which many species are found in ponds or slow-moving rivers.
  Choke pondweed, an American water weed (Anarcharis Canadensis, syn. Elodea Canadensis.) See Anacharis.
  Horned pondweed, the Zannichellia palustris, a slender, branching aquatic plant, having pointed nutlets.
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  pondweed
       n 1: any of several submerged or floating freshwater perennial
            aquatic weeds belonging to the family Potamogetonaceae
       2: submerged freshwater perennials [syn: Elodea, genus
          Elodea, ditchmoss]