Batter's role in defence (7)
I believe the answer is:
rampart
(Other definitions for rampart that I've seen before include "Battlement, fortification" , "defencework" , "Bulwark, wall" , "Fortified wall" , "Castle embankment" .)
I believe the answer is:
rampart
(Other definitions for rampart that I've seen before include "Battlement, fortification" , "defencework" , "Bulwark, wall" , "Fortified wall" , "Castle embankment" .)