noun. A detached triangular work in fortification, with two embankments which form a projecting angle.

noun. A detached work with two embankments which make a salient angle. It is raised before the curtain on the counterscarp of the place. Formerly called demilune and half-moon.

noun. A fortification outside a castle used to split an attacking force; composed of two faces, forming a salient angle whose gorge resembles a half-moon

"From the land side, it was only approachable by a causeway across the swamp, and this was guarded by a strong ravelin, which is the military name for an outwork erected beyond the ditch of a fortress."

advertent  archon  artilleryman  barbette  courts-martial  

demilune  half-moon