gabion

n. earth-filled container used for military defense; stone-filled cylinder used as a foundation for dams and dikes

Historically, gabions (from Italian gabbione meaning "big cage"; from Italian gabbia and Latin cavea meaning "cage") were round cages with open tops and bottoms, made from wickerwork and filled with earth for use as military fortifications. Modern definitions include any caged riprap for erosion control, or cylindrical metal structures used to build dams or foundations.
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n. gabion, earth-filled container used for military defense

(n.)
An openwork frame, as of poles, filled with stones and sunk, to assist in forming a bar dyke, etc., as in harbor improvement.
  

(n.)
A hollow cylinder of wickerwork, like a basket without a bottom. Gabions are made of various sizes, and filled with earth in building fieldworks to shelter men from an enemy's fire.
  

mil. hidr. gabion