water milfoil

American  

noun

1. any of various aquatic plants, chiefly of the genus Myriophyllum, the submerged leaves of which are very finely divided.

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water milfoil British  

noun

1. any of various pond plants of the genus Myriophyllum, having feathery underwater leaves and small inconspicuous flowers: family Haloragidaceae

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Etymology

Origin of water milfoil

First recorded in 1570–80

Example Sentences

Conservation officials say species like zebra mussels and Eurasian water milfoil can spread rapidly by attaching to recreational boats moved from one waterway to another.

From Washington Times

Wicken Fen is home to many rare plant species, including the marsh pea, the marsh fern, the milk parsley and the whorled water milfoil, as well as a number of different orchids.

From BBC