noun 1.excavation and piling of
earth in connection with an engineering operation.
2.Military. a construction formed chiefly of
earth for protection against enemy fire, used in both offensive and defensive operations.
3.an artistic
work that consists of a large-scale alteration or modification of an area of land in a configuration designed by an artist or of an artist's sculptural installation, as in a museum or gallery, of soil, rock, or similar elemental materials.