Pronunciation: (bak'ing),[key] —n. 1. aid or support of any kind.
2. supporters or backers collectively.
3. something that forms the back or is placed at or attached to the back of anything to support, strengthen, or protect it.
4. Theat.a curtain or flat placed behind a window, entrance, or other opening in a stage set to conceal the offstage area.
5. material for backing a joist or rafter.
6. a bevel given to the outer and upper edge of a hip rafter.
7. the musical accompaniment for a soloist; backup.