Xanthium \Xan"thi*um\, n. [NL., fr. Gr. xa`nqion a plant used for dyeing the hair yellow, said to be the Xanthium strumarium, from xanqo`s yellow.]

(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.

Source: Webster's Revised Unabridged Dictionary (1913)