caltrop

Definition

A metal object, usually small, with spikes arranged so that, when thrown onto the ground, one always faces up as a threat to pedestrians, horses, and vehicles (also used as a heraldic charge).

Etymology

From Middle English calketrappe, from Old English calcatrippe, from Medieval Latin calcatrippa (“thistle”), from Latin calx or calcare (“to tread”) + trappa (“trap”).

Example Sentences

• "[…] her father, the emperor Alexius, who reigned AD 1081-1118, ordered caltrops to be cast in front of his archers […]"
• "By Sung times, several different types of caltrops had been developed. As in earlier times, both caltrops could be made from both wood and iron..."
• "Caltrops, tetrahedrons, and similar devices are designed to puncture vehicle tires or limit foot traffic. The standard design has four points."