(WINDOW) [noun] [C] - a frame with a piece of glass in it which is used to make windows and doorsA sash window is a window which has two frames fixed one above the other that open by being moved up and down on sash cords (= ropes with weights at the end).See picture: Windows
SASH
Meaning of SASH in English
Cambridge English vocab. Кембриджский английский словарь. 2012