literary something that makes it possible for you to see and learn about a situation or experience that is different from your own:
The film provides a window on the immigrant experience.
[ C ] a transparent rectangle on the front of an envelope, through which you can read the address written on the letter inside
[ C ] the decorative arrangement of goods behind the window at the front of a shop, in addition to the window itself:
How much is the jacket in the window?
The shop windows are wonderful around Christmas time.