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.
Luxurious and versatile satin sash can be styled a number of ways! Wear tied at the front, back or side, tied in a bow, or tied in a knot. Sash width gradually widens as it extends toward a beautifully angled finished edge. Measures approximately 127 long. Center width is 2 1/2 wide.