escarpment, escarp, scarp, protective_embankment
Meaning: a steep artificial slope in front of a fortification
Meaning: a long steep slope or cliff at the edge of a plateau or ridge; usually formed by erosion
The scarp loomed before them, solid and blank.
Halfway up the scarp was a dark horizontal line of bushes, something like a hedge.
He glanced over the brink. The sheer face of the scarp fell away beneath them, plunging down to the tiny trees and rocks below.
It has a unique position on the summit of a steep and imposing scarp, rising on the north, south, and west sides of the borough out of the deep alluvial Vale of Blackmoor, the view from the Castle Green over three counties of verdant pasture--South, Mid, and Nether Wessex--being as sudden a surprise to the unexpectant traveller's eyes as the medicinal air is to his lungs.