terreplein

(obsolete military) The sloping earthen embankment behind a defensive wall.

(military) The level platform atop a wall, typically protected by a parapet and (strictly) distinguished from the slightly higher banquette used by its defenders.

(military) Any level base used by artillery in the field.

(civil engineering) Any earthen embankment with a broad level top, such as those used for a canal elevated above a valley floor.