in fortification, a kind of fence made at a passage, retrenchment, &c. to stop up the entry thereof, and is composed of great stakes, about four or five feet high, placed at the distance of eight or ten feet from one another, with transoms, or over-thwart rafters, to stop either horse or foot, that would enter or rush in with violence: In the middle is a moveable bar of wood, that opens and shuts at pleasure. A barrier is commonly set up in a void space, between the citadel and the town, in half moons, &c.

Barrier has been also used to signify a martial exercise of armed men, fighting together with swords, within rails or bars, which inclose them.

BARRING a vein, in farriery, an operation performed upon the veins of a horse's legs, and other parts of his body, with intent to stop the course, and lessen the quantity of the malignant humours that prevail there.