cal·​trop | \ ˈkal-trəp How to pronounce caltrop (audio) , ˈkȯl- \
variants: or less commonly calthrop \ ˈkal-​thrəp How to pronounce calthrop (audio) , ˈkȯl-​ \

Definition of caltrop

1a caltrops also calthrops plural in form but singular or plural in construction : star thistle sense 1
b : puncture vine also : any of various related herbs (genera Tribulus and Kallstroemia) of the same family (Zygophyllaceae, the caltrop family)
2 : 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 hooves of horses or to pneumatic tires

First Known Use of caltrop

15th century, in the meaning defined at sense 1a

History and Etymology for caltrop

Middle English caltrappe, alteration of calketrappe star thistle, from Old English calcatrippe, from Medieval Latin calcatrippa

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The first known use of caltrop was in the 15th century

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Cite this Entry

“Caltrop.” Dictionary, Merriam-Webster, Accessed 25 Feb. 2020.

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