elodea
noun
elo·dea i-ˈlō-dē-ə 
: any of a small American genus (Elodea) of submerged aquatic monocotyledonous herbs
Example Sentences
Recent Examples on the Web Plants include bacopa, elodea, stream moss, duckweed, azolla and ludwigia. 
Janene Holzberg, baltimoresun.com, 3 Sep. 2019 The Susitna River Coalition is among the participants in a task force aimed at eradicating elodea from the Mat-Su Valley. Author: Elizabeth Earl, Anchorage Daily News, 20 June 2019 The Alaska Department of Fish and Game has closed Alexander and Sucker lakes to all access this summer, specifically targeting controlling the spread of elodea. Author: Elizabeth Earl, Anchorage Daily News, 20 June 2019
Janene Holzberg, baltimoresun.com, 3 Sep. 2019 The Susitna River Coalition is among the participants in a task force aimed at eradicating elodea from the Mat-Su Valley. Author: Elizabeth Earl, Anchorage Daily News, 20 June 2019 The Alaska Department of Fish and Game has closed Alexander and Sucker lakes to all access this summer, specifically targeting controlling the spread of elodea. Author: Elizabeth Earl, Anchorage Daily News, 20 June 2019 Word History
Etymology
borrowed from New Latin, genus name, derivative from the base of Greek helṓdēs "marshy," from hélos (neuter s-stem) "wet meadow, marsh" (probably going back to Indo-European *selos- "marsh," whence also Sanskrit sáraḥ "pond, lake") + -ōdēs "like, having the nature of" (probably generalized from adjectives describing smells, as kēṓdēs "smelling like incense," from the base od- of ózein "to smell, give off odor") — more at odor
Note: Genus named by the French botanist André Michaux (1746-1802) in Flora Boreali-Americana, vol. 1 (1803), p. 20.
First Known Use
circa 1868, in the meaning defined above