Type of window made up of a number of rectangular panes of glass or louvers, placed in slots in a frame, one above the other. The panes are held in place by a pinned connection that rotates, allowing the panes to be opened simultaneously to provide a flow of air. When closed, the panes overlap slightly, preventing rain from entering the structure, however they do not seal tightly so this type of window works better in mild climates. It is often referred to as a louvered window.