1. A Batten is a pipe hanging over the stage
from which lights, curtains, scenery, and other equipment may be hung. Theaters typically use 1 1/2 inch I.D. "Schedule 40" (sometimes the stronger but heavier "Schedule 80") steel pipe. See also BIP
. Battens may be part of a fly system and able to be raised or lowered, or they may be "dead hung
" in one place. See also http://www.jrclancy.com/battens.asp
2. (noun) A batten can also refer to a piece of wood, typically a 1x4, serving much the same function as above.
3. (verb) To reinforce or repair a structural defect in a wooded structural member. Like much of theatrical rigging nomenclature, comes from a seaman's term, i.e. "Batten down the hatches."