n. - A fieldwork consisting of two faces, forming a salient angle, and two parallel flanks. See Bastion.
n. - A half horseshoe, which wants the sponge.
n. - A kind of watch crystal which is more than ordinarily flattened in the center; also, a species of convexoconcave lens for spectacles.
n. - A piece of felt to cover the eye of a vicious horse.
n. - Any surface of semicircular or segmental form; especially, the piece of wall between the curves of a vault and its springing line.
n. - An iron shoe at the end of the stock of a gun carriage.