ablaq Middle Eastern tradition of architectural decoration combining different coloured stone
antemurabilus second or outer walls
ashlar stone cut into rectangular blocks and laid in regular rows
bailey, bailli fortified enclosure with a castle
barbican outer defensive enclosure, usually outside a gate
barrel vault vaulting in the form of an elongated arch
bastion projecting or additional part of a fortification
castrum (pl. castra) fortified enclosure, usually rectangular
chatelain commander of a castle
chemin de ronde raised walkway around the circuit or curtain-walls
concentric castle fortification with two or more circuit walls
corbel stone bracket to support another structure
crenellation tooth-like projections along the top of a fortified wall to provide protection for the defenders
cubit unclear unit of measure, about half a metre
curtain wall continuous defensive wall around a fortified location
donjon main tower of a fortified location, or a single isolated tower
double-castrum fortified enclosure with two concentric defensive walls
drawbridge entrance bridge, usually over a moat, which can be raised, usually blocking the gate behind
embossed masonry blocks of stone in which the centre is raised and usually roughly cut embrasure opening in a fortified wall through which the defenders can shoot
enceinte curtain-wall
forewalls additional defensive walls in front of the main defensive walls and towers
fosse defensive ditch
galleries passages, usually within a defensive wall, sometimes with embrasures
glacis smooth slope leading to the base of a fortified wall
hoarding wooden structure in the form of a gallery mounted on top of, and also ahead of, a defensive wall
keep main tower of a fortified position (see donjon)
machicolation overhanging structure on a tower or fortified wall
merlons raised masonry forming a crenellation (see above)
oat ditch or fosse forming an obstruction outside a defensive wall
motte and bailey castle consisting of a tower on a small man-made hill (motte), with an outer fortified enclosure (bailey)
portcullis grid-like gate or iron or iron and wood, usually raised an lower into position inside a gateway
posterns small doors or gates in the defences of a fortified position
redoubt outwork of a fortified place
salient towers towers thrust forwards from a fortified wall
slot machicolation aperture above a broad groove down the face of a tower or fortified wall
spur-castle castle built on a spur or promontory, usually on the side of a hill
talus additional sloping front along the lower part of a wall and tower
undercroft lowest chamber of a multi-storey building or structure
ward open area surrounded by a curtain wall