In fortification, a demi-lune is a work constructed beyond the main ditch of a fortress, and in front of the curtain between two bastions, intended to defend the curtain; a ravelin.
Related term(s): Curtain; Bastion; Ravelin; Half-moon; Gorge; Angle, Salient
Category: Castles and Fortifications
Source information: Wilhelm, Thomas. A Military Dictionary and Gazetteer. Philadelphia: L.R. Hamersly & Co., 1881. 130.