Castle Glossary of Terms / Dictionary:

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There are so many parts of a castle, architectural jargon and archaic terms regarding medieval life that you may not be familiar with.

Throughout the Welsh Castle Project posts we’ve tried speaking in ‘Laymens terms’ to be accessible for all, but if you don’t know what something is hopefully you’ll find it here.

Anything I think may be a confusing or an unknown technical term, I’ve added it here and linked the word in question to help readers seamlessly understand our content. Once you’ve read the definition just click ‘back’ on your browser to take you back to the page you were on.

If you’ve found something on our site which you don’t know what it means and it’s not found here in the Glossary, please let us know and we’ll add a definition!


Aisle – Space between arcade and outer wall. (in a church) a lower part parallel to the nave, choir, or transept, from which it is divided by pillars.

Allure – is the passage running behind the parapet at the top of a wall or tower. See also: Wall walk, Guards Porch.

Ambulatory – Aisle round an Apse.

Ancillary Column – Vertical element with a small cross-section, added to the wall or pillar, used in church and secular construction in the period from the 11th to the 15th centuries. It performed the static transfer function, through the ribs, of the weight of the vault to the ground. Used as a structural and decorative element. The vertical ancillary column connects with the ribs of the vault, creating a unique transition between the wall and the vault.

Apse – circular or polygonal end of a tower, Chancel or chapel, A large semicircular or polygonal recess in a church, arched or with a domed roof.

Arbalestinacruciform loophole, used by crossbowmen.

Arcade, arcading -a covered passage with arches along one or both sides. Rows of arches supported on columns, free-standing or attached to a wall (blind arcade) supported on piers or columns.

Arch– can be round-headed, pointed, two-centered, or drop; ogee – pointed with double curved sides, upper arcs lower concave; lancet – pointed formed on an acute-angle triangle; depressed – flattened or elliptical; corbelled – triangular, peaked, each stone set a little further in until they meet, with a large capstone.

ArchivoltMoulded arch face, decorated with ornaments, closing the portal or any other arch at the top of the opening in the wall of the building, most often richly decorated. Archivolt was used in architecture of all periods and directions. An archivolt alone on the wall is called a blind archivolt.

Armour – a covering used to protect an object, individual, or vehicle from physical injury or damage, especially direct contact  weapons  or  projectiles  during combat, or from a potentially dangerous environment or activity. E.g. Maille, Helm, gauntlets, greeves, plakard etc.

Arrow Loop – A narrow vertical slit cut into a curtain wall or tower wall through which arrows could be fired from inside. Often cross shaped to allow more range horizontally. See also; Meurtriere

Arrow Slit –a vertical ‘window’, very narrow on the outside, spreading to a larger size one could stand in on the inside, out of which one shot, guess what, arrows. Later ones had a horizontal slot in the middle to give a wider angle of fire for crossbows.

Arsenal (AKA Armory) – A building or complex of buildings with defensive features, in which weapons and war equipment were stored. The arsenals also had workshops where repairs were made and hand-crafted or guns were repaired.

Ashlar – blocks of smooth evenly dressed, squared stone masonry of any kind neatly trimmed to shape.

Aumbry – recess to hold sacred vessels; typically in a chapel.


Bailey – Walled enclosure or courtyard of a castle; See also: Ward. The courtyard-like area of ground enclosed by a stone wall or wooden palisade, where the domestic buildings of the castle were. In a concentric castle, the area between two encircling walls.

Bailiff– person in charge of allotting work to peasants, organising repairs to castles, and doing other jobs on a medieval castle.

Ballista – Siege engine resembling a crossbow, used in hurling missiles or large arrows.

Baluster– a small column.

Balustrade– a railing, as along a path or stairway.

Barbican– also called a Hornwork. A structure built to protect the outside of an entrance. Can also be, a special kind of towered gatehouse built in two parts. The gateway or outworks defending the drawbridge. an outwork or forward extension of a castle gateway.

Bar hole– horizontal hole for timber bar used as a door-bolt.

Barmkin– the small walled yard attached to a pele tower (generally Scottish). A courtyard surrounding a tower house, defended by a perimeter wall.

Barracks– building or group of buildings used to accommodate soldiers.

Barrel vault– cylindrical/semicircular roof of stone or timber.

Bartizan– an overhanging battlemented corner turret, corbelled out; sometimes as grandiose as an overhanging gallery; common in Scotland and France. These are particularly notable in the castles of North Wales.

Base cruck– form of timber-framed construction where the roof is supported by curved timbers rising from the walls and not by aisle posts set on the floor.

Basilica Church – Christian multi-nave temple with a central nave higher than the aisles and having windows over the roofs of the aisles.

Bastion– A small tower at the end of a curtain wall or in the middle of the outside wall; solid masonry projection; structural rather than inhabitable. A gun platform projecting from an angle of the walls of a castle to expose attackers on either side to fire.

Bastion Towertower projecting from the wall face and functioning as a bastion.

Bastle House– small tower house with a living room over a byre.

Batter– also known as talus or plinth. A sloping part of a curtain wall. The sharp angle at the base of all walls and towers along their exterior surface; talus. Outward slope of a revetment.

Battery– grouping of artillery.

Battered Plinth- This refers to the base of a wall being provided with a widening slope, both to strengthen the bottom of the wall against undermining and to provide a ricochet surface for objects such as rocks being dropped down from machicolations that would bounce off horizontally.

Battering Ram (AKA Ram) – Large beam of wood capped with a metal tip. Used to break down castle gates and doors of a fortification.

Battlement– A narrow wall built along the outer edge of the wall walk to protect soldiers against attack. A crenellated parapet with indentations or embrasures, with raised portions (merlons) between; a narrow wall built along the outer edge of the wall walk for protection against attack.

Bay– internal division of building marked by roof principals or vaulting piers.

Bay window– a window projecting out from a building at ground level, either rectangular or polygonal, of one or more storeys. A window that projects out from a building above ground level is known as an oriel window.

Belfry (Or Siege Tower) – Tall, mobile tower built of wood which was wheeled up to the castle walls so attackers could storm the castle from the top of the belfry via a wooden bridge onto the castle parapet.

Belvedere– A raised turret or pavillion.

Bergfried– Defense tower. First appearing in France in the twelfth century and from there they spread in the first half of the 13th century to the German states. Initially, the bergfrieds were free-standing and were designed for passive defense, with time they were incorporated into the defenses of the castle and provided with elements that increased the ability of active defense.

Berm– Flat space between the base of the curtain wall and the inner edge of the moat; level area separating ditch from bank.

Bifora – A window or slide usually divided by a column or pillar (mullion) in two parts. Bifora was characteristic of romanesque and gothic architecture.

Billet– ornamental moulding used in Norman architecture, consisting of raised cylindrical or rectangular blocks at regular intervals.

Bivalate– a hillfort defended by two concentric ditches.

Blende – Shallow niche in wall of arcade or window appearance, used primarily for aesthetic purposes, rarely to relieve the wall, used as decoration of the gables, may be plastered in white or filled with painted tracery imitating gothic window.

Blind arcade– line of arches on the face of a solid wall for decoration.

Blockhouse– small square fortification, usually of timber bond overlapping arrangement of bricks in courses (flemish, dutch, french, etc.).

Bombard – Early form of cannon.

Bond– arrangement of bricks in courses.

Bond tenant– a tenant who was bound to provide a labour service as part of his tenure; later changed to a money payment.

Bonnet– freestanding fortification; priest’s cap.

Boss– central stone of arch or vault; key stone.

Bow– window as bay window but curved in plan.

Box Machicolation – enclosed arrowslit, overhanging on brackets outside the defensive element (defensive wall, tower, etc.) adapted to its vertical, wings and front defenses, by arrowslits and machicolation. Available only from the guard walkway or defensive floor.

Bracket (aka Corbel) – a decorative bracket, made of stone, brick or wood, embedded in the wall and protruding from it, supporting a sculpture, cornice, balcony, bay window, column or ribs of the vault.

Brattice or breteche– also known as hoarding. Timber tower or projecting wooden gallery.

Breastwork– heavy parapet slung between two gate towers; defence work over the portcullis.

Bressumer– beam to support a projection.

Broch– drystone free-standing tower with interior court, no external windows (which face into the court), spiral stair inside wall, typically Iron Age Celtic refuge in Scotland.

Bronze Age – The Bronze Age is a historic period, approximately 3300 BC to 1200 BC, that was characterized by the use of bronze, in some areas proto-writing, and other early features of urban civilization.

Bulwarkbastion or (in first half of 16th century) a blockhouse. A small tower at the end of a curtain wall.

Burh or Burg– Saxon stronghold; literally a “neighborhood”.

Buttery– from French bouteillerie, meaning storage room for beverages, next to the kitchen, a room from where wine was dispensed. The “Butler’s” room off the Great Hall. Wine cellar, serving room, silverware, etc. See also Pantry– in Norman French/English buttery means ‘bottle room’ and pantry means ‘bread room’.

Buttress– wall projection for extra support; flying – narrow, arched bridge against the structure (usually employed for cathedrals); pilaster – gradually recedes into the structure as it ascends.


Cable moulding– a Norman moulding carved like a length of rope.

Camera– private room used for both living and sleeping, set apart from the more public areas of a house.

Campshedding– facing of piles of boarding along a bank.

Cannon Tower – late medieval artillery tower much wider than the higher. Most often it was incorporated into a defensive circuit. Defense equipment were hand-gun arrowslits and artillery positions on the terrace.

Cap-house –small chamber at the top of a spiral staircase in a tower or turret, leading to the open wall-walk on the roof, often a square chamber, corbelled out from the top of a round tower.

Capital– distinctly treated upper end of a column. Capital the head of a pillar, often decorated.

Caponier– covered passage within a ditch.

Caponnière – covered passage across a ditch to an outer fortification structure such as a ravelin.

Carotid– heart-shaped.

Casemate– covered chamber for musketry or artillery. Artillery emplacements in separate protected rooms, rather than in a battery.

Casement– bomb-proof vaulted accommodation for troops, stores or guns.

Castellan– officer in charge of a castle.

Catapult or Perrier– a stone throwing engine, powered by teams of soldiers pulling on ropes.

Cavalier– raised structure containing a battery, usually sited above the centre of a bastion. Raising the battery gives a better trajectory.

Cesspit– the opening in a wall in which the waste from one or more garderobes was collected.

Chamfer– surface made by smoothing off the angle between two stone faces.

Chancel– the space surrounding the altar of a church.

Chancel Arch– The arch in the wall separating the nave of the church from the chancel. Distinction by rich decoration, change in material or in color.

Chapter House – Monastic chamber serving the monks for meetings, also the meeting room of the chapter of canons. Most often it was near the chancel or at the cloister in the east wing of monastic buildings.

Chemin de ronde– rare in Britain, very characteristic of French castles, this is the ‘crown’ at the top of a round tower, a machicolated gallery below or replacing the parapet. French castle towers also had conical roofs, but this was never common in Wales where they typically had flat tops.

Chemise wall– formed by a series of interlinked or overlapping semicircular bastions.

Cheval de frise – Defensive construction to stop cavalry a movable palisade.

Chevron– zig-zag moulding in a single or repeated ‘V’.

Citadel– heavily fortified, independent defensive structure within city walls, dominating an ancient or medieval town; in the bastion system, the strongest part of the fort.

Choir– the part of a cruciform church east of the crossing.

Clasping– encasing the angle.

Cloister– four-sided enclosure with a covered walk along each side connecting a church with the principal administrative and domestic buildings.

Clunch– hard chalky material.

Cob– unburned clay mixed with straw.

Colonnade– range of evenly spaced columns.

Columnpillar (circular section).

Commote (Welsh cwmwd, sometimes spelt in older documents as cymwd, was a secular division of land in Medieval Wales. The word derives from the prefix cym- (“together”, “with”) and the noun bod (home, abode”). The English word “commote” is derived from the Middle Welsh cymwt.

Concentric– having two sets of walls, one inside the other. A castle with two or more rings of defences, one inside the other.

Constable– official in charge of castle in owner’s absence.

Coping– covering stones.

Corbel– a bracket of projecting block of stone built into a wall during construction; step-wise construction in order to support a roof beam or some other weight, as in an arch, roof, etc.

Corbiestepped or Crowstepped– squared stones forming steps upon a gable.

Corkscrew-a circular staircase – the most economical, if not the most convenient to use, method of accessing upper floors in a vertical tower; also, easier to defend.

Corinthian– elaborately foliated capital.

Cornice– decorative projection along the top of a wall.

Counterfort/Counter-Castle (Or Siege-castle)Temporary structure built close to a besieged castle in order to blockade the castle or provide protection for attackers. The defence work of besieging force.

Counterguard– a long, near-triangular free-standing fortification within the moat.

Counterscarp– outer slope of a ditch.

Course– level layer of stones or bricks.

Courtyard– walled enclosure in a castle.

Courtyard castle– type of castle consisting of a stone curtain wall that surrounds a courtyard, with buildings built inside the courtyard, normally against the curtain wall.

Couvre Face– low rampart in the ditch, protecting the face of a ravelin; analogous in function to the counterguard and fausse braye.

Covered Way / Cowered Way– protected communication all round the works of a fortress on the outer edge of a ditch, covered by earthworks from enemy fire. Passage along the outer edge of a ditch, protected by a rampart forming the glacis; it is usually some 10 metres wide.

Creasing– shaped mark on a wall, marking the pitch of a former roof.

Crenel– the low segment of the alternating high and low segments of a battlement the ‘missing bit’ on a crenelation.

Crenelation– also known as embattled. Notched battlements at the top of a tower or wall. Where a parapet is built with evenly alternating gaps (crenels – openings) at regular intervals, allowing the defenders to shoot through the gaps and shelter behind the solid parts (merlonssquare sawteeth).

Crocket – curling leaf-shape.

Cromlech (Stone Circle) – A circle made of stones arranged vertically, often around a tomb or place of worship. Cromlechs were erected in the Neolithic and Bronze Age. Most likely a place of worship and tribal gatherings. They were often orientated along the rising or setting sun or moon at certain times of the year.

Cross-and-orb – modified cross shaped Arrowslits to accommodate gunnery.

Crossbow– weapon with a bow arranged at a right-angle to a wooden stock; it was used to shoot metal bolts.

Crosswall – interior dividing wall; structural.

Crow-steps – step-gabled end to a roof. Also called Corbie steps. Stepped gables enclosing a roof to prevent wind damage.

Crownwork– Freestanding bastioned fortification in front of main defences.

Cruciform – Cross-shaped.

Cunette– trench in the bottom of a ditch.

Cupola– hemispherical armoured roof.

Curtain Wall– a connecting wall hung between two towers surrounding the bailey. Curtain wall the perimeter wall of a fortification, or any wall within a castle that does not support a roof and is used to link towers i.e. a wall ‘hung’ between towers, a castle wall enclosing a courtyard.

Cushioncapital cut from a block by rounding off the lower corners.

Cusp– curves meeting in a point. Cusp a projecting point forming a leaf shape.

Cut – assault tower in the tracery of a gothic door-arch or window-head.

Cyclopean– drystone masonry, ancient, of huge blocks.


Dansker – A tower in the front of the castle’s defensive circuit, erected on the river or moat, serving as a latrine. Equipped with a fortified sidewalk, connecting it with the castle. Specific feature of Teutonic (german) castles.

Daub – a mud of clay mixture applied over wattle to strengthen and seal it. See also Wattle.

Dead-ground – close to the wall, where the defenders can’t shoot.

Desmene – area of land reserved for a lord.

Diaper work – decoration of squares or lozenges, Diaper is any of a wide range of decorative patterns used in a variety of works of art, such as stained glass, heraldic shields, architecture, and silverwork. Its chief use is in the enlivening of plain surfaces.

Diaphragm – wall running up to the roof-ridge.

Dog-leg – a right angle in a passageway (for example, garderobes usually had a dog-leg approach so that the air from the privy pit would not blow back directly into the room). Dog-legged– with right-angle bends.

Dog-tooth – diagonal indented pyramid. Zig-zag carving around an archway, typical of the Normans.

Dolmen – Prehistoric megalithic structure originally forming a burial chamber, covered with a mound of earth or stones. The chamber consisted of stones buried vertically into the ground and a large, usually flat capstone, which was laid on top and served as a ceiling.

Donjon – more commonly known as the Keep or Great Tower. The inner stronghold of a castle.

Dormer or Dormer window – window placed vertically in sloping roof.

Double-splayed embrasure whose smallest aperture is in the middle of the wall.

Dovecot – A building to house doves or pigeons.

Drawbridge – a heavy timber platform built to span a moat between a gatehouse and surrounding land that could be raised when required to block an entrance. A wooden bridge that could be raised and lowered, sited in front of a tower or gatehouse, across a ditch. There were basically three types: (1) a simple sliding platform over the ditch that could be pulled back, (2) a raising bridge pulled up by chains attached to the outer corners, and (3) a bridge with posts reaching out over the top, with the chains hanging vertically from the posts (this had ‘leverage’ advantages).

Dressing – carved or smoothed stonework around openings and along edges.

Dripstone – a projecting moulding above an arch or lintel to throw off surface water.

Drum Tower – a large, circular, low, squat tower built into a wall, usually shorter and wider then a normal tower.

Drystone – un-mortared masonry.

Dubbing – ceremony in which a monarch or high ranking lord gives another person the title of knight; usually involving tapping each shoulder with a sword.

Dun or Dum – an Iron Age fortified enclosure, built of dry-stone, often with galleried walls, dating from the 1st century AD.

Dungeon – The jail, usually found in one of the towers.


E-plan tower house tower house with a main block and at least two wings at right angles, dating from the 16th and 17th centuries.

Earthwork fortification made of earth mounds, banks and ditches created by excavating earth.

Eaves – the overhanging edge of a roof.

Embattled – see battlemented; crenellated.

Embrasure – also known as crenel. The low segment of the altering high and low segments of a battlement. The space between merlons on a battlemented wall, also known as a crenel. OR; The open area set inside the thickness of a wall behind a loophole or arrowslit for archers to stand in.

Enceinte – an enclosing wall, usually exterior, of a fortified place; The enclosure or fortified area of a castle.

Enclosure – castle courtyard.

Enfilade – describing the arrangement of Arrow Loops or Gun Ports whereby one could achieve a cross-fire and hit the enemy from the side.

Entresol – a low storey within two high ones (mezzanine).

Escalade – Attempting to storm a castle by scaling the walls with ladders.


Fan Vault – A vault built on ribs radiating from the wall supports, such as a cantilever, semi-column, ancillary column. Ribs are all of the same curve and spaced equidistantly, in a manner resembling a fan.

Fascine – huge bundle of brushwood for revetting ramparts or filling in ditches.

Fausse Braye – low rampart in the ditch, in front of the main fortification.

Feudalism, Feudal– social system operating in the Middle Ages, according to which land was granted to nobles in return for services.

Fillet – Characteristically rectangular or square ribbon-like bands that separate mouldings and ornaments. Fillets are common in classical architecture (in which they also may be found between the flutings of columns) and in Gothic architecture.

Finial – a slender piece of stone used to decorate the tops of the merlons, tower, balustrade, etc.

Flanking Tower – Defensive element of the medieval and ancient fortifications in the form of high-altitude structures designed to defend the front side and defend the wings of the adjacent section of the defensive circuit.

Fluting – concave mouldings in parallel. The grooves found on a column shaft or pilaster. Fluting features prominently in classical architecture; used in the columns of all the classical orders. The Doric order has 20 grooves per column, while the Ionic, Corinthian and Composite orders have 24.

Foliated – carved with leaves.

Footings – bottom part of wall.

Forebuilding – an extension to the keep, guarding it’s entrance. Forebuilding structure on the outside wall of a great tower or keep, protecting the entrance and all, or part, of the approaching staircase. A sort of ‘Barbican‘ for a Keep, it protected the entrance, which contained a grand stair and additional chambers (often a chapel over the stairs); a projection in front of a keep or donjon, containing the stairs to the main entrance.

Foregate – A defensive structure in front of the gate, a extended wall with a gate, connected to the gatehouse (neck). For additional reinforcement, a defensive sidewalk with battlement, arrowslits and drawbridges were used.

Fort, Fortress fortification designed to protect defenders who did not usually live there. A military construction or building designed for the defense of territories in warfare, and is also used to establish rule in a region

Fortification, fortified – a defensive wall or other reinforcement built to strengthen a place against attack.

Fortalice – small fort or outworks of a fortification.

Fosse – ditch.

Freestone – high quality sandstone or limestone.

Fresco – painting on wet plaster wall.

Frieze – Architectural decoration element in the form of horizontal, continuous, bas-relief or painted belt with various decorative motifs. Frieze was used for the visual division and decoration of both the façade and the interior of the building.


Gable – wall covering end of roof ridge.

Ganerbenburg – Castle in which several families shared common areas of the castle including the courtyard, well and chapel while also maintaining their own private living quarters.

Garderobe – a small latrine or toilet either built into the thickness of the wall or projected out from it; projects from the wall as a small, rectangular bartizan.

Garret – the top storey of a building within the roof.

Garrison – the soldiers who manned and occupied a castle or fort.

Gatehouse – the complex of towers, bridges, and barriers built to protect each entrance through a castle or town wall.

Gauntlet – armoured glove, often with long cuff.

Glacis – a bank sloping down from a castle which acts as a defence against invaders; broad, sloping naked rock or earth on which the attackers are completely exposed. Rampart of the Cowered Way, sloping away towards the enemy.

Gothic architecture – architectural style in Europe that lasted from the mid-12th century to the 16th century, particularly a style of masonry building characterized by cavernous spaces with the expanse of walls broken up by overlaid tracery.

Great chamber – Lord’s solar, or bed-sitting room.

Great Hall – the building in the inner ward that housed the main meeting and dining area for the castle’s residence; throne room. A great hall usually had a Solar, Buttery, Pantry, and kitchen attached to it.

Groined – roof with sharp edges at intersection of cross-vaults.

Groin – junction of two curved surfaces in a vault.

Gun-loop or gun-port – opening in a wall for a gun.

Guards Porch (aka Wall Walk) – wall-walk and arrowslits in the breastwork. The porch connected the various elements of the defensive circuit, including gates, towers and bastions, to which it was sometimes the only access. See also Allure.


Half-shaft – Roll-moulding on either side of opening.

Half-timber – The common form of medieval construction in which walls were made of a wood frame structure filled with wattle and daub.

Half-tower – type of tower that is open, or only lightly constructed, at the rear. It can be semicircular or quadrilateral.

Hall – principal living quarters of a medieval castle or house.

Hall Church – Multi-nave church of the same height aisles. Unlike in the basilica, the central nave of the hall-type church is indirectly illuminated by windows placed in the walls of the aisles. Individual naves can be covered with a common large roof or separate longitudinal gable roofs.

Hall House – a defensible two-storey building containing a hall above a basement.

Hammerbeam – roof late-medieval form of roof supported on horizontal beams (hammerbeams) projecting from the walls; it enabled the central span of the roof to be open.

Heraldry – the system of coats of arms used to identify noble families.

Herringbone – brick or stone laid in alternate diagonal courses.

Herisson – a barrier of stakes, arranged randomly in the ground to prevent a direct approach from attackers.

Hillfort Bronze or Iron Age earthwork defenses of concentric ditches and banks.

Hoardingaka Hourde, see also Brattice or Breteche: A shed-like wooden covered gallery running along the top of, and overhanging the battlements, used by besieged troops to shoot arrows and drop rocks and oil on the attacking enemy below.

Honour – large feudal estate, usually centred on a castle.

Hood – arched covering; when used as umbrella, called hood-mould.

Hornwork , Hornwalk– freestanding quadrilateral fortification in front of the main wall. ‘Horned’ structure, consisting of two demibastions, one at each end of a curtain. (See also; Barbican)


Impost – wall bracket to support arch.

Inner Curtain – the high wall the surrounds the inner ward.

Inner Ward or Inner Baileyopen area in the centre of a castle

Iron Age – in Britain from c.600 BC to Roman period.


Jamb – side posts of arch, door, or window.

Joggled – keyed together by overlapping joints.

Joist – wall-to-wall timber beams to support floor boards.

Joust – combat, put on for entertainment, in which two knights rode towards each other with lances.

Justiciar – chief political and judicial officer under Noman and early Plantagenet kings.


Keep – The inner stronghold of the castle, also known as Donjon or Great Tower. A strong stone tower; main tower; stronghold. Usually the strongest building in a castle.

Keystone – central wedge in top of arch.

Knight – man who served his lord as an armoured warrior. A man awarded a non-hereditary title by the sovereign in recognition of merit or service and entitled to use the honorific ‘Sir’ in front of his name.


L-plan tower house – distinctive Scottish form of the tower house in which a wing was added at right angles to the main tower block

Label – projecting weather moulding above a door or window to deflect rainwater.

Lancet – long, narrow window with pointed head.

Lantern – small structure with open or windowed sides on top of a roof or dome to let light or air into the enclosed space below.

Lattice – laths or lines crossing to form a network.

Leige, Leigelord – concerned with or relating to the relationship between a feudal superior and a vassal.

Lesene (Pilaster Stripe) – Flat, vertical projection in the outer wall. Lesenes originally had a constructional significance, occurring in a places exposed to the forces of distraction, that is in the axes, in which on the inside of the room there are arches from the vaults.

Lias – greyish rock which splits easily into slabs.

Light – glazing; component part of window, divided by mullions and transoms.

Lintel – horizontal stone or beam bridging an opening (window or portal).

Loggia – covered arcade or colonnade.

Longbow – large, powerful wooden bow, used to shoot arrows, often over long distances.

Loophole – narrow, tall opening, in a wall slit for light, air, or shooting through. See also Arrowloop, Gunloop, Arrowslit,

Lord – any male member of the nobility or knighthood, often holder of a castle or manor.

Louvre – opening in roof (sometimes topped with lantern) to allow smoke to escape from central hearth.

Lower Ward – (Outer Bailey) economic bailey, often erected in the last phase of development, covered by a common defense system with a middle and upper wards.

Lozenge – diamond shape.

Lunette – triangular (originally crescent-shaped) defensive structure, open at the rear, often flanking a ravelin.


Machicolation – a projection in the battlements of a wall with openings through which missiles could be dropped on besiegers. Gallery on brackets, on outside of castle or towers, with holes in floor for dropping rocks, shooting, etc. The openings in the floor of a projecting stone gallery – a stone version of timber hoarding.

Mail, Maille or chain mail– flexible armour made of interlocking metal rings.

Mangonel – stone throwing machine worked by torsion, used as a siege weapon against castles, sometimes referred to as a traction trebuchet or a torsion engine.

Mantlet – detached fortification preventing direct access to a gateway; low outer wall. Or; Mobile wooden protective shield on wheels.

Matroneum – A gallery supported by columns or pillars, opened to the interior of the church. Placed above the aisles, it is most often a separate room for the monks.

Medieval – Relating to the Middle Ages; In the history of Europe, the Middle Ages or medieval period lasted approximately from the 5th to the late 15th centuries, similar to the post-classical period of global history.

Merlon – part of a battlement, the square “sawtooth” between crenels. The high segment of the alternating high and low segments of a battlement. (Also see crenellated).

Meurtriere – arrow loop, slit in battlement or wall to permit firing of arrows or for observation. an opening in the roof of an entrance passage where soldiers could shoot into the room below. Also, water could be poured down the meurtrière to extinguish any fires the enemy might set to destroy the door.see also: Murder Holes.

Mezzanine – a low storey beween two higher ones (entresol).

Middle Ages – the period of European history from the fall of the Roman Empire in the West (5th century) to the fall of Constantinople (1453), or, more narrowly, from c. 1000 to 1453.

Middle Ward – the part between the upper ward and the lower (outer) ward, separated by a defensive circuit and gates. It was created as a result of the subsequent stages of the expansion of the upper ward, originally constituting its bailey.

Moat – a deep trench usually filled with water that surrounded a castle. Either dry or water-filled, ditch around the perimeter of a castle, manor, settlement, etc., for defence.

Moline – ends curling outward.

Mortar – a mixture of sand, water, and lime used to bind stones together; as opposed to dry laid masonry.

Motte – a mound of earth on which a tower was built; artificial conical earth mound (sometimes an old barrow) for the keep.

Motte-&-Bailey – commonly used phrase to describe a mound of earth with wood or stone keep, surrounded by ditched and palisaded enclosure (or courtyard).

Moulding – masonry decoration; long, narrow, casts strong shadows.

Mullion – vertical division of windows. The vertical divider of a window that’s constructed in panels.

Multivallate hillfort with three or more concentric lines of defence.

Mural -. Having to do with a wall. A mural tower is a tower standing on a wall.

Mural stair – staircase built within the thickness of a wall.

Murder Holes – a section between the main gate and a inner portcullis where arrows, rocks, and hot oil could be dropped from the roof though holes. Provides good cover for defenders and leaves the attacker open. Also used to drop water on to a gate that was set on fire by the enemy. See also: Meurtriere.


Nailhead – pyramid moulding.

Narthex – enclosed passage between the main entrance and nave of a church; vestibule.

Neck – fortified communication line, connecting the gate with the frontal element or defense, raised to strengthen the gate.

Neck Ditch – ditch cutting across a neck of land, to hinder an enemy’s advance.

Necking – ornament at the top of a column, bottom of the capital.

Neolithic – The Neolithic Period is characterized by fixed human settlements and the invention of agriculture from circa 10,000 BC. The final division of the Stone Age, with a wide-ranging set of developments that appear to have arisen independently in several parts of the world.

Net Vault – The type of vault, usually the barrel vault, in which intersecting ribs forming diamond mesh, which gives it the shape of the net. The vault was introduced at the end of the gothic period.

Newel – center post of spiral staircase.

Niche – vertical recess in a wall, often to take a statue.

Nookshaft – shaft set in angle of jamb or pier.

Norman, Normans – member of those Vikings, or Norsemen, who settled in northern France (or the Frankish kingdom), together with their descendants. The Normans founded the duchy of Normandy and sent out expeditions of conquest and colonization to southern Italy, England, Wales, Scotland, and Ireland.


Offset – ledge marking the narrowing of a wall’s thickness.

Ogee – a double curve, bending one way and then the other.

Oilette – a round opening at the base of a loophole or arrowloop, usually for a cannon muzzle.

Olite or Oolite – granular limestone.

Onager Roman name for a Mangonel, literally a “wild ass”. A light stone throwing engine, powered by a skein of twisted rope.

Open joint – wide space between faces of stones.

Oratory – private in-house chapel; small cell attached to a larger chapel.

Order – one of a series of concentric mouldings.

Oriel – projecting window in wall; originally a form of porch, usually of wood (similar to a hoarding, but smaller); side-turret.Oriel or Oriel Window – projecting room on an upper floor, later an upper-floor bay window

Orillons – Round or squared-off extensions of a bastion‘s faces, designed to protect its recessed flanks.

Oubliette – a dungeon reached by a trap door; starvation hole Oubliette dungeon or pit under the floor, reached by a trap-door, used for incarcerating prisoners. French translation: ‘place to be forgotten’.

Outer Bailey – complex of economic buildings, located in the immediate vicinity of the castle and organically related with it. Most often surrounded by a defensive circuit.

Outer Curtain – the wall the encloses the outer ward. The outermost curtain wall within the shell wall; otherwise, the shell wall itself.

Outer Ward – The area around the outside of and adjacent to the inner curtain.


Page – young boy of noble birth who served the household of a lord, and sometimes became a squire.

Palas (Pfalz, Palace) – the term defining the seat of the ruler, an impressive residential building, the palace of the emperor, king or bishop. In the ninth century, the buildings erected in the capital courts and fortified manors were called palases. the place of ceremonies, feasts, and the greetings of guests. Residential, administrative and economic rooms were aside.

Palisade (aka Stakewall) a sturdy wooden fence built to enclose a site until a permanent stone wall could be constructed.

Palmette – looped like a palm-leaf.

Palm Vault – A vault built on ribs radiating from one or several pillars inside the room in the middle of the span. The palm vaults were used most often in the late gothic period.

Pantile – a roof-tile of curved s-shaped section.

Pantry – associated with the Buttery in the Great Hall complex. Pantry actually means ‘bread room’ (pan French: bread). The lower end of a great hall, opposite the lord’s dais at the upper end, almost always had three doors: buttery, pantry, and passage to kitchen.

Parados – low wall in inner side of main wall, edging the wallwalk.

Parapet – low wall on outer side of main wall, edging the wallwalk. Most Parapets had merlons and crenels along the tops to form crenallations which allowed archers to shoot arrows while still being protected behind the castle walls. The protective wall at the top of a fortification, around the outer side of the wall-walk

Pavillion – a subsidiary building that is either positioned separately or as an attachment to a main building.

Peasant – a poor smallholder or agricultural labourer of low social status (chiefly in historical use or with reference to subsistence farming in poorer countries).

Pediment – low-pitched gable over porticos, doors, windows.

Pele tower aka Peel Tower – small isolated keep-like tower, built during the later Middle Ages. Small fortified keeps or tower houses built along the English and Scottish borders intended as watch towers where signal fires could be lit by the garrison to warn of approaching danger.

Peel originally a palisaded court. Later a stone tower house.

Pellet – circular boss.

Pend – an open ended passage through a building, at ground level.

Perpendicular – English architectural style (1330-1540).

Perrier – a stone throwing engine, powered by teams of soldiers pulling on ropes. See also Catapult

Petit appareil – small cubical stonework.

Petrary – Stone throwing engine. A generic term for medieval stone-throwing siege engines such as mangonels and trebuchets, used to hurl large rocks against the walls of the besieged city or castle.

Piatta Forma fortification structure protecting the curtain between two bastions; it is square or rectangular in plan, or takes the form of a small tetrahedral bastion.

Pier – support for arch, usually square.

Pikeman – soldier carrying a pike or similar long-handled weapon.

Pilaster – shallow pier used to buttress a wall.

Pillar – a tall vertical structure of stone, wood, or metal, used as a support for a building, or as an ornament or monument.

Pinnacle – ornamental crowning spire, tower, etc.

Pipe rolls – annual accounts of sheriffs rendered to the king.

Piscina – hand basin with drain, usually set against or into a wall. A shallow basin, placed next to the church altar. It was intended for washing communion vessels. Most often it was made of stone.

Pitch – roof slope.

Pitching – rough cobbling on floor, as in courtyards.

Place of Arms – enlarged area in a covered way, where troops could assemble.

Plinth – also known as talus. Projecting base of wall.

Portal – Decorative architectural frame of the entrance doors, also internal doors, in the churches, castles, town halls, richer tenements.

Portcullis – a heavy timber or metal grill that protected the castle entrance and could be raised or lowered from within the castle. It dropped vertically between grooves to block passage or barbican. A wood and metal or metal gate, welded to form a giant grid that would slide down within the entrance of the gatehouse or Hornwalk or barbican to reinforce the security of the door or to trap attackers.

Postern or Postern Gate– a small secondary gate or doorway in a tower or curtain wall, usually for peacetime use by pedestrians, Lesser or private gate.

Prow – acute-angled projection.

Puddled – made waterproof.

Putlog – beams placed in holes to support a hoarding; horizontal scaffold beam.

Putlog Hole – a hole intentionally left in the surface of a wall for insertion of a horizontal pole.


Quadrangle – inner courtyard.

Quatrefoil – four-sided or four-lobed

Quirk – V-shaped nick.

Quoin – dressed stone at angle of building.cornerstones at the corners of a building.


Ram – See; battering ram.

Rampart – defensive stone or earth wall surrounding castle. wall or bank of excavated earth surrounding a castle which was used to defend against attacks, usually topped with a palisade or stone wall.

Rath – low, circular ringwork.

Ravelin – outwork with two faces forming a salient angle; like in a star-shaped fort (basically, one of the points protruding from the fort).

Rayere – Tall narrow opening for admitting light in a thick castle wall.

Rear-arch arch on the inner side of a wall.

Redan – outwork with two faces forming a salient angle.

Redoubt – small self-contained fieldwork, a refuge for soldiers outside the main defences.

Reduit – detached, independent outwork.

Reeded – parallel convex mouldings.

Re-entrant – recessed; opposite of salient.

Reeve – peasant appointed as supervisor of work on the lord’s land.

Refectory – communal dining hall.

Relieving arch arch built up in a wall to relieve thrust on another opening.

Respond – half-pier bonded into a wall to carry an arch.

Retirata – improvised fieldwork to counter an imminent breach.

Retrenchment – interior defence works, usually consisting of a trench and parapet.

Revet – face with a layer of stone for more strength. Some earth mottes were revetted with stone to strengthen them.

Revetment – retaining wall to prevent erosion; to face a surface with stone slabs.

Rib – raised moulding dividing a vault.

Rib Vault – arched roof with ribs of raised moulding at the groins.

Ringwork– circular earthwork of bank and ditch. An earthwork castle which has no identifiable strongpoint or motte.

Roll moulding of semi-circular section.

Romanesque – the prevailing architectural style, 8-12th cent.; massive masonry, round arches, small windows, groin-and barrel-vault.

Roman period – In Britain this was specifically between 43 AD–c. 410

Rood Screen (Pulpitum) – Brick or wooden partition in cathedral or monastic churches separating space reserved for priests or monks (chancel) from the part where could stay seculars (nave).

Roofridge – summit line of roof.

Roundel – low, circular, semicircular or U-shaped tower for artillery, projecting from the wall face.

Rubble – fill; unsquared stone not laid in courses. Stone construction using irregular stones imbedded in mortar. Uncut or roughly shaped stone, for walling.

Rustication – worked ashlar stone with the faces left rough.


Sapping – undermining, as of a castle wall

Solar – originally a room above ground level, but commonly applied to the great chamber or a private sitting room off the great hall

Salient – wall projection, arrowhead.

Saltire – diagonal, equal-limbed cross.

Sally-port – small heavily fortified side door from which the defenders can rush out, strike, and retire.

Scaffolding – the temporary wooden frame work built next to a wall to support both workers and materials.

Scale – carving resembling overlapping fish scales.

Scallop – carved in a series of semi-circles.

Scappled – cut to a smooth face.

Scarp – slope on inner side of ditch.

Screens – wooden partition at the kitchen end of a hall, protecting a passage leading to the buttery, pantry, and kitchen

Screen passage – service passage screened off at the service end of a hall.

See – seat or area of authority of bishop or archbishop, also known as diocese.

Sedilia – Place in the church for the celebrant and liturgical service, usually situated in the presbytery, south of the altar. Initially, it was rather simple in form, with time it began to take more and more decorative shapes. Sedilia were often stone niches or recesses, decorated with roofs, canopies, wimpergs, trefoils or pinnacles.

Segmental – less than a semi-circle (e.g. segmental arch).

Serf – an agricultural labourer bound by the feudal system who was tied to working on his lord’s estate.

Set back/off – ledge on wall face.

Shaft – narrow column.

Shell keep – Circular or oval wall surrounding inner portion of castle; usually stores and accommodations inside the hollow walls. A keep built in the form of a high, circular or many-sided wall which encloses the area at the motte top and which has the domestic buildings adjoining the inside of the wall. The old motte-and-bailey castles were generally wooden stockades. As power was consolidated, the richer Norman lords built round stone walls on top of their mottes which were thus rendered fireproof. (At the same time, the Bailey curtain wall was also built up in stone.)

Shell wall – the wall itself, as above, without the interior buildings. The stores and accommodations might be within the shell’s hollow walls, or the walls might be solid stone and surround the donjon and various other freestanding buildings.

Sheriff – Royal official, based in a castle, who was in charge of law and order.

Shield Wall – exceptionally thick wall, protecting the castle on its most vulnerable side.

Shifting house – building where gunpowder is checked and prepared.

Shot-hole – hole for firearms, generally smaller than a gun-port .

Siege – A military operation in which enemy forces surround a town or building, cutting off essential supplies, with the aim of compelling those inside to surrender. A military blockade of a city, or fortress, with the intent of conquering by attrition, or a well-prepared assault. This derives from Latin: sedere, lit. ‘to sit’. Siege warfare is a form of constant, low-intensity conflict characterized by one party holding a strong, static, defensive position.

Siege-Castle – See Counter castle.

Siege engine – large weapon or device, such as a battering ram, Trebuchet or catapult, used to attack a castle.

Siege tower – wooden tower on wheels which attackers used to climb over castle walls. See also Belfry.

Sill – lower horizontal face of an opening.

Six-foil – six-lobed.

Sleeper – lowest horizontal timber (or low wall).

Slight – to damage or destroy a castle to render it unfit for use or occupation as a fortress.

Slit – a narrow opening in a wall for admitting light and for firing arrows.

Soffit – underside of arch, hung parapet, or opening.

Solar – upper living room , often over the great hall. A more private chamber for the lord of the castle and his family. Lord’s parlour or private quarters, can also be sleeping quarters in general.

Spandrel – area between top of a column or pier and the apex of the arch springing from it.

Spiral Stair (Corkscrew, Turnpike) – a circular staircase – the most economical, if not the most convenient to use, method of accessing upper floors in a vertical tower; also, easier to defend.

Spire – a tapering conical or pyramidal structure on the top of a building, typically a church tower.

Splay – chamfer, or sloping face.

Splayed opening – a window or door opening with angled sides in the thickness of a wall that allow more light to enter than is possible with straight sides.

Spring – level at which the springers (voussoirs) of an arch rise from their supports.

Springald – Device for projecting large bolts or stones. War engine of the catapult type, employing tension

Springer – point from which an arch or vault is struck from a wall face.

Spur – a triangular buttress used to strengthen the bottom of a round tower (giving it a square base).

Spur Castle – A spur castle is a type of medieval fortification that is sited on a spur of a hill or mountain for defensive purposes. Ideally, it would be protected on three sides by steep hillsides; the only vulnerable side being that where the spur joins the hill from which it projects.

Squinch arch arched support for an angle turret that does not reach the ground.

Squint – Observation hole in wall or room.

Squire – young man who served a knight, helping him with his horses and armour, who hoped to become a knight himself.

Stakewall – See Palisade.

Stellar Vault Rib vault in which an additional division of fields was made to create a star image. The simplest stellar vault is created when triangles are introduced instead of the diagonal ribs. Over time, additional ribs were introduced, resulting in more complicated systems, blurring the splitting of the bays, similar to net vaults.

Steward – official in charge of running a lord’s estate; managing work, keeping accounts, etc.

Stepped – recessed in a series of ledges.

Steyned – lined (like in a well).

Stockade – solid fence of heavy timbers.

Stone Age – The Stone Age was a broad prehistoric period during which stone was widely used to make tools with an edge, a point, or a percussion surface. The period lasted for roughly 3.4 million years, and ended between 4,000 BCE and 2,000 BCE, with the advent of metalworking. The Stone Age is divided into three separate periods, namely the Paleolithic (Old Stone Age), Mesolithic (Middle Stone Age), and Neolithic (New Stone Age).

Stringcourse – continuous horizontal moulding on wallface.

Stronghouse – a mansion capable of being defended.


Talus – See Batter

Tau cross – plain T cross with equal limbs.

Tenaille – low earth or masonry structure, built in the ditch to protect the curtain wall.

Terreplein – surface of rampart behind the parapet where guns are mounted.

Tower – defensive towers were placed at strategic places along the curtain wall (corners, changes of direction, mid-wall) to provide flanking protection; at first mostly square, they were built round as time went on with a resulting better field of fire. The D-shaped tower was even superior, with a defensive round side facing the field, and a square side (which allowed for more convenient rectangular rooms) facing the Ward.

Tower-house – form of small castle, common in Scotland, consisting mainly or entirely of a single tower.

Tooth-in – stones removed (or omitted) to allow another wall to be bonded into it.

Trace – circuit or fortified perimeter, also known as the enceinte.

Tracery – intersecting ribwork in upper part of window.

Transept – (in a cross-shaped church) either of the two parts forming the arms of the cross shape, projecting at right angles from the nave.

Transom – horizontal division of window; crossbar.

Traverse – small bank or wall that cuts across the line of a covered way.

Trebuchet -Extremely powerful siege engine that worked by counter balancing weights or stones to generate propulsion for a swinging wooden arm used to launch giant stones at castle walls. War engine developed in the Middle Ages employing counterpoise.

Trefoil – three-lobed.

Triforium – The windows or open-works divided into three parts. In sacred romanesque and gothic architecture also a gallery inside the church, in the thickness of the wall (as opposed to the matroneum).

Truss – a timber frame used to support the roof over the great hall.

Tufa – cellular rock; porous limestone.

Turning bridge – a drawbridge that pivots in the middle.

Turnpike – a circular staircase – the most economical, if not the most convenient to use, method of accessing upper floors in a vertical tower; also, easier to defend.

Turret – A small tower, round or polygonal; rising above and resting on one of the main towers, usually a lookout point.

Tympanum – space between lintel and arch over doorway.


Upper Ward – chronologically the oldest part of the medieval, multi-part castle. Strongly defended, housing dwellings, chapels, keep, constituting retrenchment defense.


Vassal – a holder of land by feudal tenure on conditions of homage and allegiance.

Vault – a stone arched ceiling. (A Barrel Vault was round rather than pointed in the Gothic style.)

Vestibule – an antechamber, hall, or lobby next to the outer door of a building.

Vice – spiral stair.

Vitrified – material reduced to glass by extreme heat.

Volute – spiral scroll at angle of a capital.

Voussoir – wedge-shaped stones in arch.


Wall Walk – the area along the tops of the walls from which soldiers could defend the castle, passage along the top of a castle wall; may be roofed. also the passage running behind the parapet at the top of a wall or tower. See also: Allure, Guards Porch.

Wall-plate – horizontal roof-timber on wall-top.

Wall-stair – also known as mural stair. Staircase built into the thickness of a wall.

Ward – Walled enclosure or courtyard of a castle; see also: Bailey.

Water-leaf – plain broad leaf moulding.

Wattle – a mat of woven (willow) sticks and weeds; used in wall and dike construction. (see also Daub)

Wave – sinuous moulding. A succession of wavy lines.

Weathering – sloping surface to throw off rainwater.

Westwork – western work, western wing. The western part of the basilica, characteristic of pre-romanesque architecture, located on the nave.

Wicket – person-sized door set into the main gate door.

Wimperg (Gable) – Decorative triangular finish, crowning the top of the portal or window arch, characteristic of gothic architecture. Made of stone or brick.

Wing-wall – wall downslope of motte to protect stairway.



Yett– iron lattice gate. Similar to portcullis.


Didn’t find what you were looking for?

These are the terms I thought some people may not be familiar with, but as you can see there is so much technical information within history, architecture, archaeology, geography, arms-and-armour, construction and art etc. that it’s likely I’ve missed something!

If you were reading our blog and found something you didn’t know what it was, I’ll add it to this Glossary as soon as you LET US KNOW!

- Dom and Indigo

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