brat·tice 
(brătĭs)
(brătĭs)n.
1. A partition, typically of wood or cloth, erected in a mine for ventilation.
2. A breastwork erected during a siege.
[Middle English bretice, defensive structure, from Old French bretesche, from Medieval Latin bretescha (turris), British-style (tower), probably from Old English bryttisc, British.]
brattice v.