water milfoil definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
any of a genus (Myriophyllum, family Haloragaceae) of graceful, feathery dicotyledonous plants (order Haloragales) growing under water: used in aquariums
water milfoil definition by American Heritage Dictionary
Any of various cosmopolitan aquatic herbs of the genus Myriophyllum, having feathery, finely dissected submersed leaves and entire or toothed emersed leaves.