Theatre Terms | Page 8 | AACT

Theatre Terms

image of question markAs a service to the theatre community, AACT provides over 1000 definitions of theatrical terms.  Fully searchable, our glossary is helpful for technical staff, directors, actors, producers, or anyone wanting to better understand the inner workings of theatre.

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Term Definition Link
BLOW In acting, to forget one's lines or business, as to blow the scene (from 'to blow up').
BOARD The main control for the stage lighting. Originally known as the switchboard or dimmer board, it is now usually remote from the dimmers. The lighting operator for a show is said to be "on the board".
BOOK 1) Script. One is said to be "off book" when a script is no longer permitted onstage during rehearsal. 2) The spoken lines in a musical, as distinguished from the music and lyrics.
BOOK FLAT Two-fold piece of scenery. Book flats are free-standing when angled open, allowing quick setting and compact storage. Booking describes the action of opening or closing a book flat.
BOOK SHOW A musical with a plot or storyline, as opposed to a revue.
BOOM 1) A light tree or vertical scaffolding pole on which horizontal boom arms can be mounted, carrying instruments. Often used behind wings for side-lighting etc. Booms have a base plate or stand at the bottom and are tied off to the grid or fly floor at the top (not always necessary for short booms). Booms can also be fixed to the rear of the proscenium arch or hanging from the ends of lighting bars. 2) An arm mounted on a microphone stand.
BOOTH A place, usually enclosed and at the back of the auditorium, from which an electrician can operate lighting and sound equipment.
BORDER 1) A strip of curtain stretched horizontally across the front top of the stage behind the proscenium arch, fastened to a batten and fixed, used to form the top of a setting and mask the flies and lights. When several are used, they are often numbered towards the upstage area (first border, second border, etc.) or named for the scenes painted on them (foliage border, sky border, etc.)
BOUNCE 1) Diffuse light that has been reflected from the stage, walls, cyc etc. 2) Describes the fast in/out movement of "bouncing" the flown house curtain or drape, used during curtain calls. This can also apply to the fast blackout/lights up cues that happen at curtain calls.
BOX BOOM A front-of-house vertical lighting position (predominantly sidelight).
BOX OFFICE or BOX-OFFICE An office in a theatre, commonly in the outer lobby, where tickets are sold.
BOX SET Naturalistic setting of a complete room built from flats with only the side nearest the audience (the "fourth wall") missing.
BRACE 1) Angled strengthening timber within a flat. 2) Support for scenery (flattage) on stage. An extendable brace hooks into a screw eye on the flat and is weighted to the floor (commonly known as a "Stage Brace") A French brace is a right-angled non-adjustable triangular frame, made from timber, and attached to the flat with pin hinges. Often swung flush to the flat for storage or flying.
BRACE WEIGHT Cast iron weight placed on foot of extendible or French brace to prevent movement. Often referred to as a "Stage Weight" or "Pig" (as in pig iron).
BRAIL A rope, wire or chain attached at either end of a piece of scenery or lighting bar pulling it upstage or downstage of its naturally hanging position to allow another flying item to pass, or to improve its position.
BRAVO A shouted word of applause, meaning "Excellent!" The Italian forms "brava" (for an actress) and "bravi" (for two or more actors) are also used.
BREAK A LEG A superstitious and widely accepted alternative to "Good Luck" (which is considered bad luck in the theatre).
BREAK CHARACTER In acting, saying or doing something that is not in keeping with the character one is portraying. Most often this is accidental, as when an actor forgets a line or bit of business, or when distracted by an occurrence in the audience or offstage.


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