Metal or wooden bars, rods, or framing used to consolidate and reinforce buildings or other structures. Uses include sustaining slender columns, as the supporting framework for a tent, canopy, or hanging members, and in tracery. For the skeletons or framework that support the plastic material of sculptures during modeling, use "armatures (sculpture components)."

Source: AAT

http://vocab.getty.edu/page/aat/300263491