Pronunciation: (win'dō),[key] —n. 1. an opening in the wall of a building, the side of a vehicle, etc., for the admission of air or light, or both, commonly fitted with a frame in which are set movable sashes containing panes of glass.
2. such an opening with the frame, sashes, and panes of glass, or any other device, by which it is closed.
3. the frame, sashes, and panes of glass, or the like, intended to fit such an opening: Finally the builders put in the windows. 4. a windowpane.
5. anything likened to a window in appearance or function, as a transparent section in an envelope, displaying the address.
6. a period of time regarded as highly favorable for initiating or completing something: Investors have a window of perhaps six months before interest rates rise. 7. Mil.chaff1 (def. 5).
9. Pharm.the drug dosage range that results in a therapeutic effect, a lower dose being insufficient and a higher dose being toxic.
10. Aerospace. a. See launch window. b. a specific area at the outer limits of the earth's atmosphere through which a spacecraft must reenter to arrive safely at its planned destination.
11. Computers.a section of a display screen that can be created for viewing information from another part of a file or from another file: The split screen feature enables a user to create two or more windows.
—v.t. 1. to furnish with a window or windows.
2. Obs.to display or put in a window.