Acoustics – The quality of sound in a given space measured and analysed by its clarity, loudness, liveliness, reverberance, echoes, dynamic range, envelopment, spaciousness, warmth and silence or noise control rating.
Apron – That part of the stage floor which projects forward of the proscenium toward the audience, also known as the “forestage”.
Backdrop – A suspended canvas or velour panel extending the full width of the performing area and providing the background for a performance.
Backstage – Usually used as a synonym for offstage but may include any space outside the stage house used by performers or crew.
Batten – An overhead length of steel pipe to which scenery, drapery or lighting equipment is attached. Part of the rigging system, the battens run across the stage parallel to the proscenium and are suspended from the grid.
Black Box – A type of studio theatre in which the audience and the actors are in the same room.
Boom – In stage lighting, a vertical length of pipe on which stage lighting fixtures are mounted one above the other. They are used most often for side lighting from the wings (tormentor booms) or for lighting from positions along the side walls of the auditorium (box boom).
Border – Overhead masking (curtains or canvas) that forms the upper edge of the stage picture and that conceals battens and other hanging equipment from the view of the audience. Also called “teaser.”
Bridge – A steel walkway, usually placed parallel to the stage, from which lights may be hung or operators may work.
Changeover – Preparing a theatre for a new program or show by rearranging or changing scenery, props and lighting equipment.
Control Console – Unit used for remote control of the entire stage lighting system.
Counterweight Arbor/Carriage – Device holding steel or lead weights in stacks, used to counterbalance the load suspended from a rigging batten. Moving the carriage up or down along tracks or guide wires causes the batten and its load to move in the opposite direction.
Counterweight Rigging System – A mechanical system for flying scenery. In this arrangement, lines from a rigging batten run up to loftblocks (pulleys) above a grid, and then across the top of the stagehouse to a side wall. The lines are then gathered at a headblock and directed down the side wall to the counterweight arbour.
Crossover – A corridor for performers and crew, hidden behind a backdrop or cyclorama or running behind the stagehouse, allowing passage from one side of the stage to the other out of view of the audience.
Cue – In performance, a signal for action. The term can apply to actions by the performers as well as the technical crew.
Cue Lights – A special lighting system to signal stage personnel to make an entrance or shift a scene.
Cyclorama – A neutral background, often made of fabric, at the upstage limit of the performing area, generally used to represent sky. Also known as a “cyc”.
Deck – The stage floor.
Dimmer – An electrical device that regulates the flow of current to a lighting fixture, thus controlling the intensity of the lamp.
Dimmer Bank/Dimmer Rack – An array of stage lighting dimmers and associated wiring and circuit breakers, contained in a cabinet.
Downstage – The front of the performing area; i.e., that part of the stage nearest the audience.
Dress Circle – A British term referring to the first balcony. Often referred to in North America as the mezzanine.
Electronic Memory Lighting Control – Lighting control system that stores in computer memory all cues and presets of a given stage lighting design.
Fire Curtain – A fire-resistant curtain made of asbestos, fabric or steel. In the event of a fire, the curtain is automatically lowered to isolate the stagehouse from the audience. Also known as the “Asbestos” or “Safety Curtain”.
Flat – A panel of scenery, usually constructed of canvas stretched over a wooden frame and painted. “Two fold” and “book flats” are free-standing and constructed in hinged sections.
Fly Floor – An elevated platform along the side wall of the stagehouse, from which stagehands operate the rigging system. Also known as the “Fly Gallery”.
Fly – To raise or lower scenery and equipment above the performing area by means of a rigging system.
Fly Tower – The space above the stage into which scenery and lighting equipment are raised out of sight of the audience. Also known as the “Fly Space” or simply “the Flies”.
Followspot – Movable spotlight that pivots both horizontally and vertically, allowing a stagehand to aim it at any portion of the performing area or to “follow” a performer.
Four Walls – A theatre which is offered for rental without any movable theatrical furnishings, such as stage lighting fixtures, dimming system, draperies, or related production equipment.
Front-of-House (or F.O.H.) – Any part of the theatre, such as the auditorium or lobby, which is usually accessible to the public. Front-of-house lighting positions are located in the auditorium rather than in the stagehouse.
Grid – The openwork steel floor and associated structure placed above the stage to support the stage rigging and to provide access to it.
Grid Height – The distance between the stage floor and the upper surface of the gridiron.
Hanging plot – A plan or series of drawings specifying the location of all scenery, masking, and stage lighting equipment for a particular production.
Headblock – A multigrooved drum, or sandwich of independent pulleys, at which two or more lines of a stage rigging set are gathered; the lines are directed downwards to a counterweight carriage or pin rail where they can be manipulated as a group.
House – The auditorium or seating area.
House Curtain – A decorative curtain between the auditorium and the performing area. It may be drawn open horizontally or flown vertically.
Hydraulic Stage Lift – An elevator system using fluid pressure to raise and lower the orchestra pit or sections of the stage.
Intercom System – The communications system through which the stage manager maintains voice contact with the production crew during a performance or rehearsal.
Legs – Masking curtains hung vertically and parallel to the sides of the proscenium. Legs define the sides of the performing area and hide offstage areas from the view of the audience.
Lighting Instrument – Portable stage lighting fixture, usually mounted in position with clamps.
Lighting Ladders – Steel frames on which lighting instruments are mounted. Suspended in the wings, lighting ladders leave the stage floor unobstructed.
Light Plot – A diagram showing the location of all lighting fixtures and equipment required for a given stage lighting design.
Loading Bridge – A high platform, adjacent to the stagehouse wall, used by stagehands to adjust loads in counterweight arbors.
Load-In/Load-Out – Load-in is the process of unloading from trucks, unpacking and setting up all of the scenery, costumes, sound, lighting and other equipment required for a particular production or performance. Load-out is the reverse.
Masking – Stage draperies and flats used at the side limits of the performing space to conceal offstage areas and equipment from the audience’s view. (See also Legs and Borders).
Offstage – Usually a synonym for backstage, but can include any area beyond the wings and out of sight of the audience.
On Stage – Within the performing area; in view of the audience.
Orchestra Pit – The area below the front of the stage, usually used to house the orchestra. Also known as “the Pit”.
Orchestra Rail – The railing separating the orchestra pit from the audience.
Paint Frame – A vertical frame that holds a backdrop in place for painting. It is often able to be moved up and down so that an artist can reach every part of the backdrop.
Patch Panel – Electrical switchboard allowing any branch circuit in the stage lighting system to be assigned to any dimmer.
Show relay – A communication system that carries the sound of a performance to performers and crew backstage and permits the stage manager to make announcements to all backstage locations.
Pin Rail – In a stage rigging system, the tubular steel railing fitted with belaying pins to which the free end of a rigging line is tied off.
Portal – A neutral border of wood, canvas or other material within the proscenium opening, which acts like a mat around a painting.
Preset – In stage lighting, the ability to set all dimmers at the levels required for a particular cue, in advance of executing the actual lighting change.
Producing Organization – An organization that creates its own work for performance. Management typically includes an administrative and an artistic staff.
Properties – Furniture, set decor and small, moveable items used onstage. Also known as “Props”.
Proscenium – The wall which divides the stagehouse from the auditorium. The opening through which the audience views the stage is known as the proscenium arch.
Purchase Line – Manila line pulled by a stagehand operating a counterweight rigging system. Pulling the line, which is tied to a counterweight arbour, moves the attached rigging batten and its load of scenery or other equipment.
Rake – The slope of the stage or auditorium and balcony floors. A raked stage slopes from the stage apron towards the rear wall of the stagehouse (hence the terms “upstage” and “downstage”).
Repertory – A performance schedule in which different works are presented on an alternating or rotating basis.
Rigging – The battens, lines and associated equipment required for the vertical movement of scenery.
Risers – Vertical surfaces between the steps in a stairway, or between stepped platforms.
Road Box/flight case – Large crates on wheels, used to ship a touring company’s scenery, costumes, equipment, etc.
Scene Dock – A place on or adjacent to the stage where scenery is kept when not in use.
Scenery – Built or painted elements of the stage picture, including backdrops, flats and wagons.
Scrim/gauze – A loosely woven drop, opaque to the audience when lit from the front, yet nearly transparent when lit from behind.
Sheave – Grooved wheel or pulley over which a rigging line passes when changing direction.
Side Lighting – Lighting aimed at the performing area from the wings.
Sightlines – Theatre geometry that plots an audience’s view of the performing area. Analysis of the vertical and horizontal sightlines predicts the views from different seats in the house.
Stage – The performing area and those areas offstage in its immediate vicinity, all bounded by the stagehouse walls.
Stagehand – Any stage crew member who works with scenery, props, sound or stage lighting.
Stagehouse – In a proscenium theatre, the structure containing the performing area and offstage space. The term is generally reserved for theatres with full-height, counterweight rigging systems or low-grid rigging systems.
Stage Left – To the left of a performer as he faces the audience. To the audience’s right.
Stage Right – To the right of a performer as he faces the audience. To the audience’s left.
Single Purchase Counterweight Rigging – A rigging system in which the vertical run of a counterweight arbour equals the vertical distance traveled by a flying batten.
Strike – To dismantle and load out a production following its run or to remove a piece of stage equipment from its playing position.
Tab Curtain – A curtain which opens to the sides and up, creating a draped effect.
Thrust Stage (or Thrust Theatre) – A theatre where the performing area projects into the auditorium and is surrounded by seating on three sides.
Tormentor (or Torm) – Generally refers to the first adjustable leg or portal downstage.
Traps – Removable sections of stage floor which allow access to the performing area from below.
Trim – The height at which a piece of scenery, masking or other element is intended to hang above the stage floor. To level off a piece of hung scenery to the correct height for a performance.
Tripping – Where the grid height is too low to fly backdrops completely out of view, secondary battens are used to fly the bottoms of the drops.
Upstage – The rear of the performing area; that part of the stage which is farthest from the audience.
Wings – In a proscenium theatre, the offstage spaces located to the immediate left and right of the stage.
Worklights – Lights used for the general illumination of the stage when not in performance.
