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water milfoil

American  

noun

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

water milfoil British  

noun

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of water milfoil

First recorded in 1570–80

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.