Definition of window-frame:
(n) :
An opening, usually covered by one or more panes of clear glass, to allow light and air from outside to enter a building or vehicle.
(n) :
An opening, usually covered by glass, in a shop which allows people to view the shop and its products from outside; a shop window.
(n) :
(architecture) The shutter, casement, sash with its fittings, or other framework, which closes a window opening.
(n) :
(figurative) A period of time when something is available or possible; a limited opportunity.
(n) :
(figurative) Something that allows one to see through or into something
(n) :
A restricted range.