ap·​er·​ture | \ ˈa-pər-ˌchu̇r How to pronounce aperture (audio) , ˈa-pə-, -chər, -ˌtyu̇r, -ˌtu̇r\

Definition of aperture

1 : an opening or open space : hole entered the cave through a narrow aperture
2a : the opening in a photographic lens that admits the light
b : the diameter of the stop in an optical system that determines the diameter of the bundle of rays traversing the instrument
c : the diameter of the objective lens or mirror of a telescope

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Synonyms for aperture


hole, opening, orifice, perforation

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Examples of aperture in a Sentence

We entered the cave through a narrow aperture. The photograph was taken using a fast shutter speed and a large aperture.

Recent Examples on the Web

The larger the window or other aperture to increase visibility, the greater the possibility it could be penetrated by incoming tank projectiles, small caliber rounds, or artillery shrapnel. Kyle Mizokami, Popular Mechanics, "All-Seeing HD Cameras Could Solve Tanks' Biggest Weakness," 17 Apr. 2019 These headphones also feature 45mm large-aperture drivers that offer a deep, accurate bass response. Popular Mechanics, "Get Deep Black Friday Discounts on These 10 Headphones and Earbuds," 15 Nov. 2018 Filled with desolate vistas, a feathered and furred menagerie, and multiple aperture-like windows, these fragments quickly establish a moody tone and over time become dolorous refrains. Manohla Dargis, New York Times, "Review: The Persistence of Abbas Kiarostami’s Vision in ‘24 Frames’," 1 Feb. 2018 And then there are the cameras—this is where these phones have changed the most from last year's iPhone X. Each phone has dual 12-megapixel rear cameras—wide angle at an ƒ/1.8 aperture and telephoto at ƒ/2.4. Samuel Axon, Ars Technica, "iPhone XS and XS Max review: Big screens, big performance, big lenses, big prices," 1 Oct. 2018 During Sukkot, Jews sit in a Sukkah—a temporary dwelling that in order to be kosher cannot be too tall or sturdy, and whose roof must be made of raw, unfinished vegetable matter with apertures. Eliora Katz, WSJ, "The Sunshine of the Vanities," 27 Sep. 2018 Its Lynx multimode radar is a synthetic aperture radar intended for tracking surface targets on land and sea and for providing ground imaging—but not for searching for other aircraft. Sean Gallagher, Ars Technica, "Top drone: Reaper scores drone kill in air-to-air missile test," 20 Sep. 2018 The five AUVs used in the search are equipped with side-scan sonar, multi-beam echo-sounder for seabed mapping, an HD camera, and synthetic aperture sonar. Sean Gallagher, Ars Technica, "Doomed Argentine sub found a year after its disappearance," 19 Nov. 2018 Next to the standard camera is a 16-megapixel super wide camera with a 107 degree, f/1.9 aperture lens. Dan Seifert, The Verge, "LG V40 ThinQ review: one phone, five cameras," 3 Oct. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'aperture.' 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 aperture

15th century, in the meaning defined at sense 1

History and Etymology for aperture

Middle English, borrowed from Latin apertūra, from apertus, past participle of aperīre "to open" + -ūra -ure — more at aperient

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Statistics for aperture

Last Updated

26 Apr 2019

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Time Traveler for aperture

The first known use of aperture was in the 15th century

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More Definitions for aperture



English Language Learners Definition of aperture

formal : a hole or small opening in something
technical : an opening that controls the amount of light that passes through a lens (such as a camera lens)


ap·​er·​ture | \ ˈa-pər-ˌchu̇r How to pronounce aperture (audio) \

Kids Definition of aperture

: an opening or open space : hole


ap·​er·​ture | \ ˈap-ə(r)-ˌchu̇(ə)r, -chər, -ˌt(y)u̇(ə)r How to pronounce aperture (audio) \

Medical Definition of aperture

1 : an opening or open space
2 : the diameter of the stop in an optical system that determines the diameter of the bundle of rays traversing the instrument

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Comments on aperture

What made you want to look up aperture? Please tell us where you read or heard it (including the quote, if possible).


something valued as if it were money

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