What is "demigorge"

Demigorge \Dem"i*gorge`\, n. [Cf. F. demi- gorge.] (Fort.) Half the gorge, or entrance into a bastion, taken from the angle of the flank to the center of the bastion.

n. (context military English) Half the gorge, or entrance into a bastion, taken from the angle of the flank to the centre of the bastion.