abattis
advanced work
balistraria
bank
banquette
barbed-wire entanglement
barbican
barricade
barrier
bartizan
bastion
battlement
breastwork
bulwark
casemate
cheval-de-frise
circumvallation
contravallation
counterscarp
curtain
demibastion
dike
drawbridge
earthwork
enclosure
entanglement
escarp
escarpment
fence
fieldwork
fortalice
fortification
glacis
loophole
lunette
machicolation
mantelet
merlon
mound
outwork
palisade
parados
parapet
portcullis
postern gate
rampart
ravelin
redan
redoubt
sally port
scarp
line of defence
line of defense
abbatis
birk
bowshot
crossroad
depositary
drinking-water
horsepond
lable
landmark
maquis
midnight
millrace
opy
peekaboo
pourer
powerline
quickset
rampire
springe
sycamore-tree
theheart
ultracapacitor
work-around