From Middle English windowe, from Old Norse vindauga, equivalent to .

• (British) IPA: /ˈwɪndəʊ/
• (America) enPR: wĭnʹdō, IPA: /ˈwɪndoʊ/
• (some accents) enPR: wĭnʹdə, IPA: /ˈwɪndə/

window

1. 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.
   • 1879, R[ichard] J[efferies], chapter 1, in The Amateur Poacher, London: Smith, Elder, & Co., […], →OCLC ↗:

     But then I had the [massive] flintlock by me for protection. ¶ […] The linen-press and a chest on the top of it formed, however, a very good gun-carriage; and, thus mounted, aim could be taken out of the window at the old mare feeding in the meadow below by the brook, and a 'bead' could be drawn upon Molly, the dairymaid, kissing the fogger behind the hedge, […].

   • 1952, L. F. Salzman, Building in England, page 173:

     A window is an opening in a wall to admit light and air.

   • 1963, Margery Allingham, chapter 14, in The China Governess: A Mystery, London: Chatto & Windus, →OCLC ↗:

     Nanny Broome was looking up at the outer wall.  Just under the ceiling there were three lunette windows, heavily barred and blacked out in the normal way by centuries of grime.

2. An opening, usually covered by glass, in a shop which allows people to view the shop and its products from outside; a shop window.
   • 1915, G[eorge] A. Birmingham [pseudonym; James Owen Hannay], chapter I, in Gossamer, New York, N.Y.: George H. Doran Company, →OCLC ↗:

     There is an hour or two, after the passengers have embarked, which is disquieting and fussy. […] Passengers wander restlessly about or hurry, with futile energy, from place to place. Pushing men hustle each other at the windows of the purser's office, under pretence of expecting letters or despatching telegrams.

3. (architecture) The shutter, casement, sash with its fittings, or other framework, which closes a window opening.
4. (figurative) A period of time when something is available or possible; a limited opportunity.

   launch window

   window of opportunity

   You have a two-hour window of clear weather to finish working on the lawn.

5. (figurative) Something that allows one to see through or into something

   His journal provides a rare window into his otherwise obscure life.

6. A restricted range.
   • 2015, Patrick R. Nicolas, Scala for Machine Learning, page 109:

     In this case, a band-pass filter using a range or window of frequencies is appropriate to isolate the frequency or the group of frequencies that characterize a specific cycle.

7. (graphical user interface) A rectangular area on a computer terminal or screen containing some kind of user interface, displaying the output of and allowing input for one of a number of simultaneously running computer processes.
8. A figure formed of lines crossing each other.
   • 1709, William King, Art of Cookery:

     till he has windows on his bread and butter

9. (medicine) The time between first infection and detectability.
10. (military, historical, uncountable) Synonym of chaff
11. (signal processing) A function multiplied with a signal to reduce spectral leakage when performing a Fourier transform.

• eye
• wind

• French: fenêtre
• German: Fenster, Windauge, Luke
• Italian: finestra
• Portuguese: janela
• Russian: окно́
• Spanish: ventana, fenestra

• French: fenêtre
• German: Intervall, Zeitraum, Zeitspanne, Zeitfenster
• Italian: finestra
• Portuguese: intervalo (período de tempo)
• Russian: окно́
• Spanish: ventana

• French: fenêtre
• German: Fenster
• Italian: finestra
• Portuguese: janela
• Russian: окно́
• Spanish: ventana

• French: fenêtre, côté fenêtre

window (windows, present participle windowing; simple past and past participle windowed)

1. (transitive) To furnish with windows.
2. (transitive) To place at or in a window.
   • c. 1606–1607 (date written), William Shakespeare, “The Tragedie of Anthonie and Cleopatra”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC ↗, [Act IV, scene xiii]:

     Wouldst thou be windowed in great Rome and see / Thy master thus with pleach'd arms, bending down / His corrigible neck?

3. (transitive, signal processing) To apply a window function to (a signal).