caltrop

American  

[kal-truhp] / ˈkæl trəp /

Also calthrop

noun

1. any of several plants having spiny heads or fruit, as those of the genera Tribulus and Kallstroemia, or the star thistle, Centaurea calcitrapa.

2. an iron ball with four projecting spikes so disposed that when the ball is on the ground one of them always points upward: used to obstruct the passage of cavalry, armored vehicles, etc.

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caltrop British  

/ ˈkælθrəp, ˈkæltrəp /

noun

1. any tropical or subtropical plant of the zygophyllaceous genera Tribulus and Kallstroemia that have spiny burs or bracts

2. another name for water chestnut

3. another name for the star thistle

4. military a four-spiked iron ball or four joined spikes laid upon the ground as a device to lame cavalry horses, puncture tyres, etc

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Etymology

Origin of caltrop

before 1000; Middle English calketrappe, Old English calcatrippe, colte-træppe, equivalent to calce- (< Latin calci-, stem of calx spur, heel) + træppe trap ¹

Example Sentences

The first taste concentrates all the senses into a tightly packed knot of jagged steel edges trapped halfway along the back of the leg, like a small caltrop buried tightly within the flesh.

From Slate • Jun. 25, 2013

Sooner or later, the worm forsakes this kind of caltrop which catches on to everything.

From The Life of the fly; with which are interspersed some chapters of autobiography by Teixeira de Mattos, Alexander

VII., was "a ton, out of which issues some plant, perhaps a caltrop, which might be contracted to the first syllable of his name."

From Notes and Queries, Number 203, September 17, 1853 A Medium of Inter-communication for Literary Men, Artists, Antiquaries, Genealogists, etc. by Bell, George