Plural of caltrap; sharp four-pronged devices scattered on ground to puncture tires or injure feet, or the spiky plant that produces similar shapes.
From Middle English 'caltrap,' combining 'calt' (possibly from Latin 'calx' meaning heel) and 'trap.' The word originally described both the military weapon and the naturally occurring spiked plant genus Tribulus, which has seed pods resembling the weapon.
Medieval armies literally weaponized the shape of a plant's seeds—caltraps were so effective at stopping cavalry charges that they appear in military records from ancient Rome through World War II, and some versions are still used in law enforcement today.
Complete word intelligence in one call. Free tier — 50 lookups/day.