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