tropical annual procumbent poisonous subshrub having fruit that splits into five spiny nutlets; serious pasture weed

[ Syn: devils weed , tribulus terestris ]

a plant of the genus Trapa bearing spiny four-pronged edible nutlike fruits

[ Syn: water chestnut , water chestnut plant ]

Mediterranean annual or biennial herb having pinkish to purple flowers surrounded by spine-tipped scales; naturalized in America

[ Syn: star-thistle , centauria calcitrapa ]