1. Lighting. Shortened form of pipe stiffener.
2. Scenic. AKA "batten stiffener" or "stiffening batten" (the board, not the counterweight fly system pipe), a type of horizontal, lateral reinforcement for a wall of flats (either flat, Broadway or flat, Hollywood), sometimes (depending on how pedantic one is) synonymous with hog trough, whaler, or strongback. See http://www.controlbooth.com/forums/question-day/20391-whaler-hogs-trough.html for discussion.
2. Scenic. AKA "batten stiffener" or "stiffening batten" (the board, not the counterweight fly system pipe), a type of horizontal, lateral reinforcement for a wall of flats (either flat, Broadway or flat, Hollywood), sometimes (depending on how pedantic one is) synonymous with hog trough, whaler, or strongback. See http://www.controlbooth.com/forums/question-day/20391-whaler-hogs-trough.html for discussion.