An envelope with a transparent panel on its front, through which the name and address of the addressee printed on the letter inside can be seen.

A window that opens and closes by sliding a pane, as opposed to folding in or out. / (programming) A descriptor for a data analysis technique where overlapping windows of data of fixed size are analyzed.

A period of time, often in which a task is to be done

A (originally detachable) second window attached on the exterior side of a window in climates with harsh winters, to add an insulating layer of still air between the outside and inside.

plural of window box

(intransitive) To engage in window-shopping; to browse the windows of shops with no intention of buying anything.

The decorative display of retail merchandise in store windows; the goods and trimmings used in such a display. / (uncountable) The process, skill or task of creating such a display.

A narrow box filled with earth, placed on a windowsill and used for growing plants. / One of the hollows in the sides of a window frame for the weights which counterbalance a lifting sash.

A person whose job is to clean windows. / A product, such as Windex, used to clean windows.

The wooden, aluminium or PVC etc. framework around a window