burdock

noun

1. a composite plant of the genus Arctium, especially A. lappa, a coarse, broad-leaved weed bearing prickly heads of burs that stick to the clothing.

noun

1. a coarse weedy Eurasian plant of the genus Arctium, having large heart-shaped leaves, tiny purple flowers surrounded by hooked bristles, and burlike fruits: family Asteraceae (composites)