milfoil noun. ['mɪlfɔɪl] ME.
[Old French milfoil (mod. MILLEFEUILLE) from Latin milefolium, millef-, from Latin mile, mille a thousand + folium leaf (see FOIL noun¹), after Greek muriophullon (from murios myriad + phullon leaf).]
1. Any of various plants of the genus Achillea, of the composite family, with feathery finely divided leaves; esp. yarrow, A. millefolium. ME.

2. In full water milfoil. Any of various aquatic plants constituting the genus Myriophyllum (family Haloragaceae), which have whorled finely pinnate leaves and spikes of inconspicuous flowers. L16.

[TahlilGaran] English Dictionary ▲