Schloss

Schloss (pl. Schlösser) is a German word for a building similar to a Château, castle or palace. Most Schlösser were built after the Middle Ages for representative purposes and not for defense.

shiro

Japanese castles (城 ,shiro) were fortresses composed primarily of wood and stone. They evolved from the wooden stockades of earlier centuries, and came into their most well-known form in the 16th century. Like European castles, the castles of Japan were built to guard important or strategic sites, such as ports, river crossings, or crossroads, and almost always incorporated the landscape into their defense.

motte-and-bailey

A motte-and-bailey is a form of castle. Many were built in Britain, Ireland and France in the 11th and 12th centuries, favoured as a relatively cheap but effective defensive fortification that could repel most small attacks .

murder-hole

A murder-hole or meurtrière is a hole in the ceiling of a gateway or passageway in a fortification through which the defenders can fire, throw or pour dangerous or noxious substances at attackers. As a result, the defenders would be able to rain rocks, arrows, heated sand, boiling oil, water and incendiary devices, and other substances down on the attackers' heads. Similar holes, called machicolations, were often located in the curtain walls of castles, fortified manor houses and city walls. The parapet would project over corbels so that holes would be located over the exterior face of the wall, and arrows could be shot at, rocks dropped on, or boiling water poured over, any attackers near the wall.

keep

A keep is a strong central tower which is used as a dungeon or a fortress. Often, the keep is the most defended area of a castle, and as such may form the main habitation area, or contain important stores such as the armoury, food, and the main water well, which would ensure survival during a siege.

portcullis

A portcullis is a latticed grille or gate made of wood, metal or a combination of the two. Portcullises fortified the entrances to many medieval castles, acting as a last line of defense during time of attack or siege. Each portcullis was mounted in vertical grooves in castle walls and could be raised or lowered quickly by means of chains or ropes attached to an internal winch.

Crenellations

Sequence of solid parts and the intervals between them along the top of a parapet, to facilitate firing and provide protection.

source
wiki