FinnHun Finnish-Hungarian-English on-line dictionary and thesaurus

n An opening; an open space; a gap, cleft, or chasm; a passage perforated; a hole; as, an aperture in a wall.

n (optics) Something which restricts the diameter of the light path through one plane in an optical system.

n (context|astronomy|photography) The diameter of the aperture (in the sense above) which restricts the width of the light path through the whole system. For a telescope, this is the diameter of the objective lens. e.g. a telescope may have a 100 cm aperture.

n (context|spaceflight|communications) The (typically) large-diameter antenna used for receiving and transmitting radio frequency energy containing the data used in communication satellites, especially in the geostationary belt. For a comsat, this is typically a large reflective dish antenna; sometimes called an array.

n (mathematics|rare|of a right circular cone) The maximum angle between the two generatrix|generatrices.