Căl'trap or Căl'trop, n.
n. [A-S. coltræppe, a species of thistle, Fr. chausse-trape, star-thistle, trap; It. calcatreppo, calcatreppolo, star-thistle, from cal-care, to tread, and tribolo, star-thistle, steel-trap, from Lat. tribulus, caltrop, a kind of thorn or thistle.]
Sense 1. (Bot.) A genus of plants (Tribulus), having a fruit composed of five nuts united in a sub-globular whorl armed with prickles, resembling the military instrument of the same name. It grows in Southern Europe among corn, and is very troublesome, as the prickles run into the feet of cattle. London.
Sense 2. (Mil.) An instrument with four iron points, so disposed that, three of them being on the ground, the other projects upward. They are scattered on the ground where an enemy's cavalry are to pass, to impede their progress by endangering the horses' feet. Holinshed.
