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A region of the earth's atmosphere where ionization caused by incoming solar radiation affects the transmission of radio waves. It extends from a height of 70 kilometers (43 miles) to 400 kilometers (250 miles) above the surface.
i·on′o·spher′ic (-sfîr′ĭk, -sfĕr′-) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
the region of the earth's atmosphere between the stratosphere and the exosphere, consisting of several ionized layers and extending from about 50 to 250 mi. (80 to 400 km) above the surface of the earth.
i•on`o•spher′ic (-ˈsfɛr ɪk) adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
A region of the Earth's atmosphere in which atoms are often ionized (electrically charged) by radiation from the sun. The ionosphere lies mostly in the lower thermosphere, from about 43 to 250 miles (69 to 402.5 kilometers) above the Earth. Radio waves, which normally travel in a straight line, can be transmitted long distances over the curved surface of the Earth because they bounce off certain layers of the ionosphere and return to Earth instead of continuing into space.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
That part of the atmosphere, extending from about 70 to 500 kilometers, in which ions and free electrons exist in sufficient quantities to reflect electromagnetic waves.
Dictionary of Military and Associated Terms. US Department of Defense 2005.
the outermost part of the earth’s permanent atmosphere, beyond the stratosphere, composed of heavily ionized molecules. It extends from about 50 to 250 miles above the surface of the earth. Cf. exosphere.See also: Atmosphere
-Ologies & -Isms. Copyright 2008 The Gale Group, Inc. All rights reserved.
1. The upper layer of the atmosphere that lies above the stratosphere and is about 217 mi (350km) thick.
2. The area of the Earth’s atmosphere in which ionization caused by solar radiation affects the transmission of radio waves.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited
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|Noun||1.||ionosphere - the outer region of the Earth's atmosphere; contains a high concentration of free electrons|
atmosphere, air - the mass of air surrounding the Earth; "there was great heat as the comet entered the atmosphere"; "it was exposed to the air"
D region, D-layer - the lowest region of the ionosphere (35 to 50 miles up) that reflects low-frequency radio waves
Appleton layer, F layer, F region - the highest region of the ionosphere (from 90 to 600 miles up) which contains the highest concentration of free electrons and is most useful for long-range radio transmission
E layer, E region, Heaviside layer, Kennelly-Heaviside layer - a region of the ionosphere (from 50 to 90 miles up) that reflects radio waves of medium length
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
ionosphere[aɪˈɒnəsfɪəʳ] N → ionosfera f
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005
n → Ionosphäre f
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007
ionosphere[aɪˈɒnəˌsfɪəʳ] n → ionosfera
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995