Xanthium

The Cockleburs (Xanthium) are a genus of flowering plants in the family Asteraceae, native to the Americas and eastern Asia. They are coarse, herbaceous annual plants growing to 50-120 cm tall. The leaves are spirally arranged, with a deeply toothed margin. Some species, notably X. spinosum, are also very thorny with long, slender spines at the leaf bases. The flowers are of two types; One, in short terminal branches, produces only pollen. The other, in clusters in the axils of the leaves, produces seed.
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Noun
1. coarse herbs having small heads of greenish flowers followed by burrs with hooked bristles
(synonym) genus Xanthium
(hypernym) asterid dicot genus
(member-holonym) Compositae, family Compositae, Asteraceae, family Asteraceae, aster family
(member-meronym) cocklebur, cockle-bur, cockleburr, cockle-burr

(n.)
A genus of composite plants in which the scales of the involucre are united so as to form a kind of bur; cocklebur; clotbur.
  

XANTO