of or relating to a semiautomatic exposure system in which the photographer presets the aperture and the camera selects the shutter speed.
- Aperture ratio
- Aperture synthesis
(in radio astronomy) a technique that combines the inputs of a set of radio telescopes to obtain a greater resolution of images than is possible with a single member of the set. noun an array of radio telescopes used in radio astronomy to simulate a single large-aperture telescope. Some such instruments use movable dishes while […]
having no petals. Historical Examples Rivina, ri-vī′na, n. a genus of apetalous plants, the pokeweed family. Chambers’s Twentieth Century Dictionary (part 3 of 4: N-R) Various Our genera are apetalous and with the calyx free from the ovary. The Manual of the Botany of the Northern United States Asa Gray Stackhousia juncea, according to Clarke, […]
- Apex beat
apex beat apex beat n. A pulsation, either visible or palpable or both, made by the apex of the left ventricle of the heart as it strikes the chest wall in systole. Historical Examples The position of the apex beat alone can not determine this, neither can the limit to the right of the sternum. […]