aperture

[ ap-er-cher ]

noun

1. an opening, as a hole, slit, crack, gap, etc.
2. Also called aperture stop. Optics. an opening, usually circular, that limits the quantity of light that can enter an optical instrument.

aperture

/ ˈæpətʃə /

noun

1. a hole, gap, crack, slit, or other opening
2. physics
   1. a usually circular and often variable opening in an optical instrument or device that controls the quantity of radiation entering or leaving it
   2. the diameter of such an opening See also relative aperture

Other Words From

• ap·er·tur·al [ap, -er-ch, oo, r-, uh, l], adjective
• ap·er·tured adjective

Word History and Origins

Origin of aperture¹

1400–50; late Middle English < Latin apertūra an opening, equivalent to apert ( us ) opened (past participle of aperīre; aper ( i )- ( aperient ) + -tus past participle suffix) + -ūra -ure

Word History and Origins

Origin of aperture¹

C15: from Late Latin apertūra opening, from Latin aperīre to open

Example Sentences

I currently still have an aperture, which means a tear above my cords.

From Los Angeles Times

Fractions of a second count and he can change apertures and focuses with a flick of his finger without taking his eyes from his quarry.

From BBC

Pushing the aperture or the F-stop down as low as possible allows the most light in, and he suggests setting the ISO as high as possible without adding grain to the image.

From Los Angeles Times

To reduce the overall system size, the researchers used small telescopes with an optical aperture of 47 mm as the receiving optics.

From Science Daily

“The implication is clear: expand the aperture wide enough and we are all related,” Halperin said.

From New York Times