Any of a number of flowering plants in the family Zygophyllaceae, including several members of the genus Kallstroemia and the species Tribulus terrestris, native to warm temperate and tropical regions.
A small, metal object with spikes arranged so that, when thrown onto the ground, one always faces up as a threat to pedestrians, horses, and vehicles.
The starthistle, Centaurea calcitrapa, a plant with sharp thorns.
The same object represented as a heraldic charge.
Any of several flowering plants of the subtribe Helianthinae.
Any of several seaducks, of the genus Bucephala, having black and white plumage.
Any of several lacewings of the family Chrysopidae.