- caltrop, devil's weed, Tribulus terestris - tropical annual procumbent poisonous subshrub having fruit that splits into five spiny nutlets; serious pasture weed
--1 is a kind of subshrub, suffrutex
--1 is a member of Tribulus, genus Tribulus - water chestnut, water chestnut plant, caltrop - a plant of the genus Trapa bearing spiny four-pronged edible nutlike fruits
--2 is a kind of aquatic plant, water plant, hydrophyte, hydrophytic plant
--2 is a member of Trapa, genus Trapa
--2 has particulars:water caltrop, Jesuits' nut, Trapa natans; ling, ling ko, Trapa bicornis - star-thistle, caltrop, Centauria calcitrapa - Mediterranean annual or biennial herb having pinkish to purple flowers surrounded by spine-tipped scales; naturalized in America
--3 is a kind of centaury