Ca'ltrops. n.s. [colꞇꞃæpp, Saxon.]

1. An instrument made with three spikes, so that which way soever it falls to the ground, one of them points upright, to wound horses feet.

   The ground about was thick sown with caltrops, which very much incommoded the shoeless Moors. Dr. Addison's Account of Tangiers.

2. A plant.

   It is very common in the South of France, Spain, and Italy, where it grows among corn, and on most of the arable land, and is very troublesome to the feet of cattle; for the fruit being armed with strong prickles, run into the feet of the cattle, which walk over the land. This is certainly the plant which is mentioned in Virgil's Georgick, under the name of tribulus. Miller.