ˈkal.trəp, -ˈȯ- noun
also cal·throp -thrəp
( -s )
Etymology: Middle English calketrappe, a plant, from Old English coltetræppe, calcatrippe, from Medieval Latin calcatrippa, probably from (assumed) calcitrappa, from calci- (from Latin calc-, calx heel) + trappa trap, of Germanic origin; akin to Old English træppe trap — more at calk , trap
1. : any of several plants having stout spines on the fruit or flower heads: as
a. : star thistle
b. : a plant of either of two genera ( Tribulus and Kallstroemia ) of the family Zygophyllaceae
c. : water chestnut
2.
a. : a device with four metal points so arranged that when any three are on the ground the fourth projects upward as a hazard to the hoofs of horses or to pneumatic tires — see caltrap
b. : a calk on a horseshoe