1. glacis - Noun
2. Glacis - Proper noun
A gentle slope, or a smooth, gently sloping bank; especially (Fort.), that slope of earth which inclines from the covered way toward the exterior ground or country (see Illust. of Ravelin).
Source: Webster's dictionaryAncient British hill forts started to incorporate glacis around 350 BC. Source: Internet
Each trench brings the infantry across the whole width of the leading edge; the first is out of range of the defenders and can withstand an assault from the rear; the third is at the foot of the glacis. Source: Internet
Anti-tank mines which employ a tilt-rod fuze are also designed to detonate directly underneath the glacis plate. Source: Internet
More generally, the term glacis can denote any slope, natural or artificial, which fulfils the above requirements. Source: Internet
In a head-on-head armored engagement, the glacis plate is the largest and most obvious target available to an enemy gunner. Source: Internet
The walls were seven feet (2.1 meters) high and fourteen feet (4.3 meters) thick, and the whole works was surrounded by a glacis and a dry moat five feet (1.5 meters) deep and convert wide. Source: Internet