cocklebur > define

Any coarse weed of the genus Xanthium having spiny burrs.
- synonyms: cockle-bur, cockleburr, cockle-burr
Burdock having heart-shaped leaves found in open woodland, hedgerows and rough grassland of Europe (except extreme N) and Asia Minor; sometimes cultivated for medicinal and culinary use.
- synonyms: great burdock, greater burdock, Arctium lappa

(n.) A coarse, composite weed, having a rough or prickly fruit; one of several species of the genus Xanthium; -- called also clotbur.

by Webster's Revised Unabridged Dictionary