A Batten

1. A thin strip of wood used in construction to hold members of a structure together or to provide a fixing point.
2. (nautical) A long strip of wood, metal, fibreglass etc., used for various purposes aboard ship, especially one inserted in a pocket sewn on the sail in order to keep the sail flat.
3. In stagecraft, a long pipe, usually metal, affixed to the ceiling or fly system in a theater.
4. The movable bar of a loom, which strikes home or closes the threads of a woof.