abatis
acropolis
advanced work
balistraria
bank
banquette
barbed-wire entanglement
barbican
barricade
barrier
bartizan
battlement
beachhead
blockhouse
breastwork
bridgehead
bulwark
bunker
casemate
castle
cheval-de-frise
circumvallation
citadel
contravallation
counterscarp
curtain
demibastion
dike
donjon
drawbridge
earthwork
enclosure
entanglement
escarp
escarpment
fasthold
fastness
fence
fieldwork
fort
fortalice
fortification
fortress
garrison
garrison house
glacis
hold
keep
loophole
lunette
ravelin
defence
defence force
defense
defense force
munition
bastille
bastioned
battlements
bluff
buttress
crag
gateway
headland
minaret
moat
palisade
parapet
pinnacle
rampart
redoubt
spire
stockade
stronghold
terrace
turret
Sebastian