• WordNet 3.6
    • n aperture an man-made opening; usually small
    • n aperture a device that controls amount of light admitted
    • n aperture a natural opening in something
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Webster's Revised Unabridged Dictionary
    • Aperture An opening; an open space; a gap, cleft, or chasm; a passage perforated; a hole; as, an aperture in a wall. "An aperture between the mountains.""The back aperture of the nostrils."
    • Aperture The act of opening.
    • Aperture (Opt) The diameter of the exposed part of the object glass of a telescope or other optical instrument; as, a telescope of four-inch aperture .
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Century Dictionary and Cyclopedia
    • n aperture The act of opening out or unfolding.
    • n aperture An opening; a hole, orifice, gap, cleft, or chasm; a passage or perforation; any direct way for ingress or egress.
    • n aperture In geometry, the space between two intersecting right lines.
    • n aperture In optics, the diameter of the exposed part of the object-glass in a telescope or other optical instrument. The aperture of a microscope is often expressed in degrees; and in this case it is called the angular aperture, that is, the angular breadth of the pencil of light which the instrument transmits from the object or point viewed: as, a microscope of 100° aperture.
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Chambers's Twentieth Century Dictionary
    • n Aperture a′pėrt-ūr an opening: the space through which light passes in an optical instrument: a hole.
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Webster's Revised Unabridged Dictionary
L. apertura, fr. aperire,. See Aperient
Chambers's Twentieth Century Dictionary
L. aperturaaperīre, to open.


In literature:

In the windows, as well as in the door, were small apertures for firing through.
"The Border Boys Across the Frontier" by Fremont B. Deering
I still had my eyes glued to the aperture in the blind, when Smith began tugging at my arm.
"The Devil Doctor" by Sax Rohmer
The webs of spiders were woven across it; across the aperture.
"Bakemono Yashiki (The Haunted House)" by James S. De Benneville
The aperture is elongated and narrow, with rather prominent lips.
"Journal of the Proceedings of the Linnean Society - Vol. 3" by Various
There was a large stone across the aperture, over which the horse had to straddle.
"The Lone Ranche" by Captain Mayne Reid
Through this aperture Edwin could see the busy, eager forms of his father, Big James, and Chawner.
"Clayhanger" by Arnold Bennett
When the range has been short and the velocity high, it is often difficult to discriminate between the two apertures.
"Surgical Experiences in South Africa, 1899-1900" by George Henry Makins
A gleam of light came through an aperture in the upper part of the wall.
"The Woodcutter of Gutech" by W.H.G. Kingston
V2 emerges from the foramen rotundum, and V3 from the foramen ovale, two apertures uniting behind a bony screen.
"Text Book of Biology, Part 1: Vertebrata" by H. G. Wells
Fearing this would sometimes prove too hot for it, I had some bricks put in to fill up the aperture.
"Anecdotes of the Habits and Instinct of Animals" by R. Lee

In poetry:

Then he tied the hands and feet of the poor child,
Which caused it to scream with fear, very wild;
Then he stole back to the aperture to effect an entrance,
And when Hanchen saw him, she said now is my chance.
"Hanchen, the Maid of the Mill" by William Topaz McGonagall

In news:

Otherwise, if you have purchased photo-editing software such as Adobe Elements, Photoshop, Lightroom, or Apple Aperture, those applications can resize photos.
Whether placed on its side or upright, the Runt 's boundary-compliant design based upon Sound Physics Labs' Unity Summation Aperture allows the unit to be used directly on a physical boundary without "self-interference".
Greg used a Canon Eos 1D camera and 600mm f4 lens set at 200 ISO, 1/1290 of a second shutter speed, and F6.4 aperture.
OnOne Software Announces Availability of Perfect Photo Suite 5.5 for Adobe Photoshop, Adobe Photoshop Lightroom and Apple Aperture.
New version of Perfect Resize and direct integration with Lightroom and Aperture provide photographers with essential tools to quickly achieve high-quality results.
At 50mm the lens's maximum aperture is f/5.6, and it scores an impressive 1,875 lines there.
These include the 15-40 mm hand held zoom model that weighs in at 4.4 pounds and has an effective aperture speed of T2.6.
The Optimo DP Series offers a focal length of 30-80mm, aperture of T:2.8, calibrated focus marks and no ramping or breathing.
A crotch region supports a plurality of absorbent pads within the garment and front and rear panels comprise a laterally-oriented trapezoidal aperture in one of the front and rear panels.
The very large men stood outside the very small basement door of my urban row house, holding a new washing machine, dubiously eyeing the aperture through which they'd have to pass.
Andor Technology's Revolution DSD white light confocal spinning disk is based on 'aperture correlation.
The Sony 16-50mm f/2.8 Standard Zoom Lens ($699.99 direct) is a fast, fixed-aperture zoom that is compatible with APS-C Sony Alpha D-SLR like cameras.
Aperture in a fully-contained system.
Coils with rectangular openings reduced to just a few centimeters, circular aperture coils with reduced metal free zones, and special detectors for the examination of individual tablets are all available.
The Aperture and Lightroom support in HDR Expose 2 is seamless: The included plug-ins pass images to the app for editing , then put them back into the collections from which they came.

In science:

The larger the aperture w, the larger the intensity in the focus and the smaller the size of the spot.
Paraxial propagation of a quantum charge in a random magnetic field
However, in the presence of the random magnetic field, the intensity saturates when the aperture w ∼ L2 /f and θ ∼ (L/f )2 .
Paraxial propagation of a quantum charge in a random magnetic field
Aperture photometry was performed on all of the standard stars in the frames, and an aperture correction was determined for each filter.
QSOs and Absorption Line Systems Surrounding the Hubble Deep Field
The SExtractor “best estimate” (using either adaptive aperture or corrected isophotal photometry; Bertin & Arnouts 1996) of the total flux for each ob ject, was used for magnitude calculations.
QSOs and Absorption Line Systems Surrounding the Hubble Deep Field
SExtractor was also run on the standard star frames in order to compare the aperture-corrected and SExtractor magnitude estimates.
QSOs and Absorption Line Systems Surrounding the Hubble Deep Field