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

Examples of caltrop in a Sentence

Recent Examples on the Web The book’s cover image reflects the internal shape of the novel: a caltrop. Caroline Hallemann, Town & Country, "Outlander Season 7: Everything We Know So Far," 14 Mar. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'caltrop.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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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Time Traveler for caltrop

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

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Last Updated

28 Mar 2021

Cite this Entry

“Caltrop.” Dictionary, Merriam-Webster, Accessed 6 May. 2021.

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