Xanthium

Definitions

  • WordNet 3.6
    • n Xanthium coarse herbs having small heads of greenish flowers followed by burrs with hooked bristles
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Webster's Revised Unabridged Dictionary
    • n Xanthium (Bot) A genus of composite plants in which the scales of the involucre are united so as to form a kind of bur; cocklebur; clotbur.
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Century Dictionary and Cyclopedia
    • n xanthium A genus of composite plants, of the tribe Helianthoideæ and subtribe Ambrosieæ. It is characterized by unisexual flower-heads, the male with a single row of separate bracts, the female armed with numerous hooked prickles. Twenty-one species have been described, perhaps to be reduced to four; they are mostly of uncertain, perhaps of American, origin, but are now widely naturalized throughout warm regions. They are coarse weedy annuals with alternate leaves which are lobed and closely tomentose, or are coarsely toothed and greenish. The small monœcious flower-heads are solitary or clustered in the axils; in the fertile heads the fruit forms a large spiny bur containing the achenes. The species are known as cockle-bur, or as clotbur; 3 occur in the United States, only 1 of which is a native, X. Canadense, which varies near the coast and the Great Lakes to a dwarf variety, echinatum, known as sea-burdock; of the others, X. spinosum, the spiny clot-bur, thought to be a native of Chili, is armed with slender yellowish trifld spines in the axils; and X. strumarium is the common species of Europe. In England it is known as ditch-bur, burweed, louse-bur, and small burdock.
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Chambers's Twentieth Century Dictionary
    • n Xanthium zan′thi-um a weedy plant of the aster family
    • Xanthium Also Cockle-bur, Clot-bur
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Etymology

Webster's Revised Unabridged Dictionary
NL., fr. Gr. xa`nqion a plant used for dyeing the hair yellow, said to be the Xanthium strumarium, from xanqo`s yellow