Not too happy with you using autism to call someone dumb, but I'll leave this up assuming it was just a one-off.
Definition of sash for Students. 1  1 : a frame for a pane of glass in a door or window. 2  2 : the movable part of a window.
The name hung sash window is more usual in the United States, and typically refers to a double-hung window with two sash that can move up and down in the window frame.These windows are commonly found in older buildings in warmer climates as they are easy to clean and promote airflow. single hung window has two sash but normally the top sash is fixed and only the bottom sash slides. Triple and quadruple hung windows are used for tall openings, common in New England churches. Construction is usually of softwood, and these sash were traditionally only single-glazed.