Castle.

Lists- Area of some size enclosed by a stockade and located around the castle.Space between two enceintes or between an enceinte and a moat which in peace time was used for tournaments (hence the expression "to enter the lists").

Chemise-Wall enclosing the base of the keep to defend it. 
(or Jacket wall)  - Inner walled enclosure of a castle. Low enceinte closely encircling the base of a tower, usually the keep.

Bartizan-A sentry box projecting from a wall used to survey the surrounding area. An overhanging battlemented corner turret, corbelled out; sometimes as grandiose as an overhanging gallery; common in Scotland and France.

Moat-Water-filled trench protecting the castle’s ramparts. A deep trench (in Europe usually filled with water) that surrounded a castle.

Stockade-The castle’s first line of defence, made up of a row of pickets or boards. 

Solid fence of heavy timbers.

Parapet-walk-Passageway along a wall, making it possible to shoot and perform surveillance.

Low wall on outer side of main wall. 

Postern-Secret door built into a rampart.  A side or less important gate or (sometimes hidden) door into a castle; usually for peacetime use by pedestrians.

Brattice, (bretèche)-Small box or machicolation projecting from the wall to reinforce its defence. Timber tower or projecting wooden gallery; hoarding. Small overhanging defensive structure often placed before the entrance of a passage way. A corbelled external gallery commanding the foot of a wall.

Battlement-Wall allowing defenders of the fortification to fire from a protected position. 

Parapet with indentations or embrasures, with raised portions (merlons) between; crenelations; a narrow wall built along the outer edge of the wall walk for protection against attack.

chapel-Place of worship.

keep-Castle’s main tower, serving as a final stronghold in the event of attack. (small keep) - A strong stone tower; main tower; donjon; stronghold. 

pinnacle-Steeple-shaped ornament atop the keep. Ornamental crowning spire, tower, etc.

Ornamental crowning spire, tower, etc.

footbridge

Narrow bridge used to cross the moat and reach the drawbridge.

barbican

Freestanding defense with arrow slits used to defend the castle’s footbridge. The gateway or outworks defending the drawbridge. Known from Antiquity, it seems to have been introduced into western architecture during the Crusades. The outwork usually circular separated from the rest of the fortress by a moat and protecting the main accesses. It forms a filter between the outside and inside of the fortress and serves as a shield, also called a hornwork.

rampart

Thick wall that formed the castle’s outer defense.

drawbridge

Movable bridge that was lowered to allow people to cross the moat and raised to prevent access to the castle.

machicolation

Balcony made of masonry with apertures in the floor through which projectiles were dropped on assailants.

guardhouse

Structure serving as living quarters for the guards.

corbel

Stone projection on a wall to support the top of a tower or wall.

curtain wall

Stone wall connecting two towers or bastions.

bailey

Uncovered space bordered by the castle’s buildings and curtain walls.

covered parapet walk

Covered corridor constructed along a battlement and designed to allow the free movement of guards.

flanking tower

Defense tower making it possible to fire a shot parallel to the curtain wall.

turret

Small watchtower.

castle

Apartments of the lord and his family.

corner tower

Circular tower allowing surveillance and defense in all directions.