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 (kăl′trəp, kôl′-)
2. Any of various plants bearing small spiny fruits, especially of the genera Tribulus and Kallstroemia.
3. A metal device with four projecting spikes so arranged that when three of the spikes are on the ground, the fourth points upward, used as a hazard to pneumatic tires or to the hooves of horses.

[Middle English calketrappe, from Norman French and from Old English calcatrippe, thistle, both from Medieval Latin calcatrippa, thistle : possibly from Latin calcāre, to tread on; see calque + trappa, trap (of Germanic origin).]


(ˈkæltrəp) or




1. (Plants) any tropical or subtropical plant of the zygophyllaceous genera Tribulus and Kallstroemia that have spiny burs or bracts
2. (Plants) water caltrop another name for water chestnut1
3. (Plants) another name for the star thistle
4. (Military) military a four-spiked iron ball or four joined spikes laid upon the ground as a device to lame cavalry horses, puncture tyres, etc
[Old English calcatrippe (the plant), from Medieval Latin calcatrippa, probably from Latin calx heel + trippa trap1]


or cal•trap

(ˈkæl trəp)

also cal•throp


1. any of several plants having spiny heads or fruit, as those of the genera Tribulus and Kallstroemeria.
2. an iron ball with four projecting spikes, one of which always points upward when the ball is placed on the ground: used to obstruct cavalry, vehicles, etc.
[before 1000; Middle English calketrappe, Old English calcatrippe]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.caltrop - tropical annual procumbent poisonous subshrub having fruit that splits into five spiny nutletscaltrop - tropical annual procumbent poisonous subshrub having fruit that splits into five spiny nutlets; serious pasture weed
genus Tribulus, Tribulus - annual or perennial herbs or subshrubs of warm regions
subshrub, suffrutex - low-growing woody shrub or perennial with woody base
2.caltrop - a plant of the genus Trapa bearing spiny four-pronged edible nutlike fruitscaltrop - a plant of the genus Trapa bearing spiny four-pronged edible nutlike fruits
genus Trapa, Trapa - small genus of Eurasian aquatic perennial herbs: water chestnut
Jesuits' nut, Trapa natans, water caltrop - a variety of water chestnut
ling, ling ko, Trapa bicornis - water chestnut whose spiny fruit has two rather than 4 prongs
aquatic plant, hydrophyte, hydrophytic plant, water plant - a plant that grows partly or wholly in water whether rooted in the mud, as a lotus, or floating without anchorage, as the water hyacinth
3.caltrop - Mediterranean annual or biennial herb having pinkish to purple flowers surrounded by spine-tipped scales; naturalized in America
centaury - any plant of the genus Centaurea
References in classic literature ?
Arms: Azure, three caltrops in chief over a fess sable.
A blue Audi hatchback was seen in the Claymore Drive and Caltrop Place area around the time of the robbery and we are keen to identify the driver.
CALTROP provided oversight and refurbishments made to the Tunnel Boring Machine (TBM), including PLC and VFD ($2.
Next, the Hong Kong defender, codenamed Caltrop, is armed with a JS9 SMG and said to have a toxic mine with a cloaking ability that will make the device difficult to spot.
The single biggest caltrop to getting an event like this off the ground is sheer ego.
Twenty one food items, which included 18 fish species, zebra mussel, and debris of aquatic vegetation including water caltrop, Trapa natans, fruits were identified in pikeperch gut contents.
lasiostachys western vervain Zygophyllaceae Caltrop Family Tribulus terrestris L.
Many are obviously related to guns, such as AR500-Targets, (4) which makes a metal target that is the shape of a tetrahedron, like a medieval caltrop.
The distinctive horned fruits of Trapa, commonly known as water chesnut or water caltrop, are among the most intensively studied and most easily recognized fossils in the Lythraceae (Fig.
It appears to have burned down several times and military-style arrowheads have been found in one of the posts, while a caltrop turned up close to the entrance.
Smack one of the angled impact plates and just like the caltrop it resembles, the Impact-45 jumps, dances and boogies, always landing with a target stickin' up