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aperture |
Also found in: Dictionary/thesaurus, Medical, Legal, Wikipedia, Hutchinson | 0.04 sec. |
apertureAn orifice. It often refers to an opening in which light is allowed to pass in optical systems such as cameras and lasers. See f-stop and numerical aperture. aperture Physics a. a usually circular and often variable opening in an optical instrument or device that controls the quantity of radiation entering or leaving it b. the diameter of such an opening aperture [′ap·ə‚chər] (electronics) An opening through which electrons, light, radio waves, or other radiation can pass. (graphic arts) A rectangular cutout on an aperture card. (optics) The diameter of the objective of a telescope or other optical instrument, usually expressed in inches, but sometimes as the angle between lines from the principal focus to opposite ends of a diameter of the objective. How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
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| The cyst tract was excised, and the piriform aperture was closed using Stenosis of the nasal piriform aperture is believed to occur secondary to overgrowth of the medial portion of the Endoscopic examination detected a somewhat darkish-red submucosal mass in the left piriform aperture of the nasal cavity. |
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