aperture

noun
ap·​er·​ture | \ˈa-pər-ˌchu̇r, 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

Synonyms

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

Microsoft went to a new display design that uses a different transistor, with a smaller pixel but a greater aperture. Mark Hachman, PCWorld, "Microsoft launches next-gen Surface Pro 6, Surface Laptop, Surface Studio and more," 2 Oct. 2018 The Columbia-Class will utilize Virginia-class’ fly-by-wire joystick control system and large-aperture bow array sonar. Fox News, "Navy mulls acceleration of first nuclear-armed Columbia ballistic missile sub," 6 June 2018 However, a telescope with an aperture of at least 6 inches is usually recommended for visual observations of this planet; magnifications of 150 to 200 power should provide the best views. Joe Rao, Space.com, "Mars Makes Its Closest Approach in 15 Years This Summer: How to See It," 29 May 2018 The other instrument is a large-aperture laser angle reflector for ranging measurements between Earth and the spacecraft. Eric Berger, Ars Technica, "China takes a critical first step toward landing on the far side of the Moon," 21 May 2018 The researchers confirmed that the facility remains active by using a new type of satellite imagery known as synthetic-aperture radar. New York Times, "Deep in the Desert, Iran Quietly Advances Missile Technology," 23 May 2018 That likely means the Note 9 will get the same dual-aperture trick that the Galaxy S9 picked up earlier this year, which was supposed to help the phone better expose for bright environments. Jacob Kastrenakes, The Verge, "Samsung reportedly plans Galaxy Note 9 announcement on August 9th," 1 June 2018 The main addition for 2018 is a new camera, which is expected to have a variable aperture. Ron Amadeo, Ars Technica, "Here’s our first clear look at the Samsung Galaxy S9," 26 Jan. 2018 The Columbia-Class will utilize Virginia-class’ fly-by-wire joystick control system and large-aperture bow array sonar. Kris Osborn, Fox News, "Navy mulls acceleration of first nuclear-armed Columbia ballistic missile sub," 30 May 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

6 Dec 2018

Look-up Popularity

Time Traveler for aperture

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

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More Definitions for aperture

aperture

noun

English Language Learners Definition of aperture

: a hole or small opening in something

: an opening that controls the amount of light that passes through a lens (such as a camera lens)

aperture

noun
ap·​er·​ture | \ˈa-pər-ˌchu̇r \

Kids Definition of aperture

: an opening or open space : hole

aperture

noun
ap·​er·​ture | \ˈap-ə(r)-ˌchu̇(ə)r, -chər, -ˌt(y)u̇(ə)r \

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

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