Definitions
1.nounA defensive mound of earth or a wall with a broad top and usually a stone parapet; a wall-like ridge of earth, stones or debris; an embankment for defensive purpose.
2.nounA defensive structure; a protective barrier; a bulwark.
3.nounThat which defends against intrusion from outside; a protection.
4.noun(usually in the plural) A steep bank of a river or gorge.