Definition of arrow weed in English:
arrow weed
noun
1Arrowhead (genus Sagittaria).
2US An evergreen shrub native to southwestern United States and northern Mexico, Pluchea sericea (family Asteraceae), which grows in dense thickets and has greyish-green leaves, clusters of purple flowers, and stiff straight stems formerly used by North American Indians to make arrows; compare arrowwood .
Origin
Mid 19th century.
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