Baluster: One of a series of short vertical posts, often ornamental, used to support a rail.
Balustrade: A railing composed of balusters and a top rail running along the edge of a porch, balcony, roof, or stoop.
Came: A slender rod of cast lead, with or without grooves, used in casements and stained-glass windows to hold the panes or pieces of glass together
Capital: The topmost member, usually decorated, of a column or pilaster.
Cast Iron: A type of iron, mass-produced in the nineteenth century, created by pouring molten iron into a mold; used for ornament, garden furniture, and building parts.
Colonnade: A row of regularly spaced columns supporting an entablature.
Colonnette: A diminutive column which is usually either short or slender.
Column : A vertical, cylindrical support. In classical design it is composed of a base (except in the Greek Doric order), a long, gradually tapered shaft, and a capital.
Console: A scroll-shaped projecting bracket that supports a horizontal member.
Corbel : An architectural member which projects upward and outward from a wall that supports a horizontal member.
Cornice: A projecting molding that tops the elements to which it is attached; used especially for a roof or the crowning member of an entablature, located above the frieze.
Cresting: A decorative element, frequently of iron, usually located at the peak or edge of a roof.
Crocket: An ornamental foliate form placed at regularly spaced intervals on the slopes and edges of the spires, pinnacles, gables, and similar elements of Gothic buildings.
Cupola: A small dome on a base crowning a roof
Decorative Masonry: Terra cotta, cast-stone or natural stone (such as limestone, marble, brownstone or granite) facade areas and/or any ornamental feature which is a component of the facade such as, belt courses, banding, water tables, cornices, corbelled brick work, medallions, enframements, and surrounds, and ornamental bonding patterns, e.g. tapestry brick or diaper patterns.
Dentil : A small, square, tooth-like block in a series beneath a cornice.
Doric: One of five classical orders, recognizable by its simple capital. The Greek Doric column has a fluted shaft and no base; the Roman Doric column may be fluted or smooth and rests on a molded base.
Egg and dart: An ornamental band molding of egg forms alternating with dart forms.
Eyebrow dormer: A curved dormer with no sides, covered by a smooth protrusion from the sloping roof.
Fanlight: A semicircular or semielliptical window above a door, usually inset with radiating glazing bars.
Fascia: A horizontal, flat element often combined with a cornice and architrave.
Fenestration: The arrangement, proportioning and design of windows in a building.
Festoon: A carved ornament in the form of a band, loop, or wreath, suspended from two points; also called a “garland” or “swag”.
Finial: The crowning ornament of a pointed element, such as a spire.
Foliate: Decorative leafage, often applied to capitals or moldings.
French door or French window: A tall casement window that reaches to the floor, usually arranged in two leaves as a double door.
Frieze: 1. The middle horizontal member of a classical entablature, above the architrave and below the cornice. 2. A similar decorative band in a stringcourse, or near the top of an interior wall below the cornice.
Gable: The upper portion of an end wall formed by the slope of a roof.
Gothic Sash : A window sash pattern composed of mullions that cross to form pointed arches.
Grille: A decorative, openwork grating, usually of iron, used to protect a window, door, or other opening.
Improvement: Any building, structure, place, work of art, or other object constituting a physical betterment of real property, or any part of such betterment.
Ionic: One of the five classical orders, characterized by capitals with spiral elements called “volutes,” a fasciated entablature, continuous frieze, dentils in its cornice, and by its elegant detailing.
Jigsaw Carving: Wooden ornament cut with a thin narrow saw blade.
Keystone: The central wedge-shaped member of a masonry arch; also used as a decorative element on arches in wood structures.
Leaded window: A window composed of small panes, usually diamond-shaped or rectangular, held in place by narrow strips of cast lead.
Lintel: A horizontal structural element over an opening which carries the weight of the wall above it.
Lunette: A crescent-shaped or semicircular area or opening on a wall surface.
Modillion: A projecting scroll-shaped bracket or simple horizontal block arranged in series under the soffit of a cornice.
Molding: A piece of trim that introduces varieties of outline or curved contours in edges or surfaces as on window jambs and heads. Moldings are generally divided into three categories: rectilinear, curved and composite-curved.
Mullion: A vertical primary framing member that separates paired or multiple windows within a single opening.
Newel: The main post at the foot of a stairway or stoop.
Oriel: A projecting bay window carried on corbels or brackets.
Pediment: 1. The triangular space forming the gable end of a roof above the horizontal cornice. 2. An ornamental gable, usually triangular, above a door or window.
Pier: 1. A column designed to support concentrated load. 2. A member, usually in the form of a thickened section, which forms an integral part of a wall; usually placed at intervals along the wall to provide lateral support or to take concentrated vertical loads. 3. A vertical supporting member or element (usually of brick, stone, or metal) placed at intervals along a wall, which typically separate each storefront opening from the adjacent storefront opening.
Pilaster: An engaged pier or pillar, often with capital and base.
Portico: A small porch composed of a roof supported by columns, often found in front of a doorway.
Quoin A structural form, usually of masonry, used at the corners of a building for the purpose of reinforcement, frequently imitated for decorative purposes.
Relief: Carved or molded ornament that projects from a flat surface.
Restoration: The process of returning, as nearly as possible, a building or any of its parts to its original form and condition.
Rosette: A round floral ornament, usually carved or painted.
Round arch: A semicircular arch.
Sidelight: A vertically framed area of fixed glass, often subdivided into panes, flanking a door.
Swag: A carved ornament in the form of a draped cloth or a festoon of fruit or flowers.
Terra cotta: Hard fired clay, either glazed or unglazed, molded into ornamental elements, wall cladding, and roof tiles.
Tracery: An ornamental configuration of curved mullions in a Gothic sash.
Trefoil: A three-lobed decorative form used in Gothic architecture
Volute: A carved spiral form in classical architecture; often used in pairs as in the capitals of Ionic columns.
Voussoir: A wedge-shaped component of an arch.
Wrought Iron: Iron that is worked by being forged or hammered.
Source: New York City Landmarks Preservation Commission website