From Longman Dictionary of Contemporary Englishapertureap‧er‧ture /ˈæpətʃə $ ˈæpərtʃʊr/ noun [countable] 1 HOLE formal a small hole or space in something2 TCPthe small hole at the front of a camera, which can be made larger or smaller to let more or less light in when you take a photograph
Examples from the Corpus
aperture• The telescope has an aperture of 2.4 metres.• The three of them watched in breathless silence as the doors reached their maximum aperture.• Lightning flickered in the ragged aperture where the ground-floor staircase door had been.• Her sculptures are hybrids of organic and machine forms: cylinders punctuated with round apertures and protuberances.• I had to get the aperture right.• As with telescopes, the larger the aperture the greater the light-grasp, but there are hazards too.• Binoculars of this aperture cost a great deal of money.• The box has 10 tiny apertures through which viewers can see 3-D images.Origin aperture (1600-1700) Latin apertura, from aperire “to open” 