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window

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

: 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

Full Definition of WINDOW

a : 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 (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>

: a means of entrance or access; especially : a means of obtaining information <a window on history>

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

: the transparent panel or opening of a window envelope

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

: chaff 4

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

a : 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>

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

: 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

— win·dow·less \-dō-ləs, -də-\ adjective

— out the window

: out of existence, use, or consideration

See window defined for English-language learners

See window defined for kids

Origin of 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

First Known Use: 13th century

Other Building Terms

batten, cistern, hearth, lath, transom, wainscot

WINDOW Defined for Kids

window

noun win·dow \ˈwin-dō\

Definition of WINDOW for Kids

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

: the glass and frame that fill a window opening

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

— win·dow·less adjective <a windowless room>

Word History of WINDOW

To people living in cold regions around the world, a window in a house was only practical when glass became available to provide light while sealing out the weather. As a result, in English and other languages of northern Europe, words for “window” appear relatively late, after glass was introduced from southern Europe. In Old English, “window” was ēagduru, literally “eye-door,” or ēagthyrel, “eye-hole”—since a window, like an eye, is a means of seeing out. The word window itself comes from a word vindauga in Old Norse (the language of the Vikings) that means literally “wind-eye.”

Medical Dictionary

window

noun win·dow \ˈwin-(ˌ)dō, -də(-w)\

Medical Definition of WINDOW

: fenestra 1

: a small surgically created opening : fenestra 2a

: 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