noun, often attributive
win·dow | \ˈwin-(ˌ)dō \

Definition of window 

1a : an opening especially in the wall of a building for admission of light and air that is usually closed by casements or sashes containing transparent material (such as glass) and capable of being opened and shut

b : windowpane

c : a space behind a window of a retail store containing displayed merchandise

d : an opening in a partition or wall through which business is conducted a bank teller's window

2 : a means of entrance or access especially : a means of obtaining information a window on history

3 : an opening (such as a shutter, slot, or valve) that resembles or suggests a window

4 : the transparent panel or opening of a window envelope

5 : the framework (such as a shutter or sash with its fittings) that closes a window opening

7 : a range of wavelengths in the electromagnetic spectrum to which a planet's atmosphere is transparent

8a : an interval of time within which a rocket or spacecraft must be launched to accomplish a particular mission

b : an interval of time during which certain conditions or an opportunity exists a window of vulnerability

9 : an area at the limits of the earth's sensible atmosphere through which a spacecraft must pass for successful reentry

10 : any of various rectangular boxes appearing on a computer screen that display files or program output, that can usually be moved and resized, and that facilitate multitasking

out the window

: out of existence, use, or consideration

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Other Words from window

windowless \ˈwin-dō-ləs, -də- \ adjective

Examples of window in a Sentence

She opened a window to let in some air. I looked out the window and saw a deer. He used vinegar and water to wash the windows. He accidentally broke a window. Can you roll down the car window? The windows along 5th Avenue were all decorated for Christmas. I saw a beautiful dress in the window. He sits behind a window and sells movie tickets. Make sure the address shows through the window in the envelope. A window opened in the fog and we could finally see the ocean.
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Recent Examples on the Web

For those who stay, the visitors councils provide a window on the wider world—and on their own regions. The Economist, "America’s amateur diplomats," 5 July 2018 Expecting something more celebratory, Luce was shocked by the final work, which depicts the young woman in mid-fall from the window of her Central Park South apartment building — and also, in the same image, dead and bleeding on the pavement. Kerry Lengel, azcentral, "How the Phoenix Art Museum acquired Frida Kahlo’s 'Suicide' painting," 13 July 2018 By the time firefighters contained the blaze, the roof had collapsed, the grand oak staircase was reduced to kindling, and fat icicles hung like stalactites from the windows. Inga Saffron,, "A tale of two historic Philadelphia buildings: One rises from the ashes. The other falls to the wrecking ball.," 12 July 2018 Someone crept up to Mason’s bedroom window in the middle of the night and fired through the glass, shooting the 19-year-old three times in his chest, prosecutors and defense attorneys said. Tim Prudente,, "Anne Arundel judge to decide 2013 murder case against Odenton man," 12 July 2018 Watch out for cracks and holes on or near doors and windows. Marc Saltzman, USA TODAY, "You can slash home energy costs by just replacing light bulbs," 11 July 2018 Repair or replace old and torn screens in doors, windows and vents. Sarah Brookbank,, "West Nile detected in North Avondale, but don't panic, it's normal," 11 July 2018 Prevent future problems by giving your curtain a chance to dry out: Turn on the exhaust fan while showering, open the door or window afterwards, and keep your curtain open instead of pushed to the side. Caroline Picard, Good Housekeeping, "Test Your Housekeeping Knowledge: How Gross Are Your Cleaning Habits?," 10 July 2018 The company makes doors, windows and hurricane shutters. David Lyons,, "Nervous South Florida industries await tariff war fallout," 6 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'window.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of window

13th century, in the meaning defined at sense 1a

History and Etymology for window

Middle English windowe, from Old Norse vindauga, from vindr wind (akin to Old English wind) + auga eye; akin to Old English ēage eye — more at eye

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Statistics for window

Last Updated

10 Oct 2018

Look-up Popularity

Time Traveler for window

The first known use of window was in the 13th century

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More Definitions for window



English Language Learners Definition of window

: an opening in a wall, door, etc., that usually contains a sheet of glass

: a sheet of glass that covers an opening in a building, vehicle, etc.

: a large window at the front of a store where goods are displayed so that they can be seen by people who are walking past


win·dow | \ˈwin-dō \

Kids Definition of window

1 : an opening in a wall to let in light and air

2 : the glass and frame that fill a window opening

3 : any of the areas into which a computer display may be divided and on which different types of information may be shown

Other Words from window

windowless adjective a windowless room


win·dow | \ˈwin-(ˌ)dō, -də(-w) \

Medical Definition of window 

2 : a small surgically created opening : fenestra sense 2a

3 : a usually narrow interval of time or range of values for which a certain condition or an opportunity exists coma and multiorgan failure can occur within hours and there may be a very narrow window of opportunity for transplantation— J. P. A. Lodge — see therapeutic window

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More from Merriam-Webster on window

Spanish Central: Translation of window

Nglish: Translation of window for Spanish Speakers

Britannica English: Translation of window for Arabic Speakers Encyclopedia article about window

Comments on window

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