milfoil

Mil"foil, n. Etym: [F. mille-feuille, L. millefolium; mille thousand + folium leaf. See Foil a leaf.] (Bot.) Defn: A common composite herb (Achillea Millefolium) with white flowers and finely dissected leaves; yarrow. Water milfoil (Bot.), an aquatic herb with dissected leaves (Myriophyllum).

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