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ionosphere

[ahy-on-uh-sfeer] /aɪˈɒn əˌsfɪər/
noun
1.
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 miles (80 to 400 km) above the surface of the earth.
Origin
1925-1930
1925-30; iono- + -sphere
Related forms
ionospheric
[ahy-on-uh-sfer-ik] /aɪˌɒn əˈsfɛr ɪk/ (Show IPA),
adjective
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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British Dictionary definitions for ionospheric

ionosphere

/aɪˈɒnəˌsfɪə/
noun
1.
a region of the earth's atmosphere, extending from about 60 kilometres to 1000 km above the earth's surface, in which there is a high concentration of free electrons formed as a result of ionizing radiation entering the atmosphere from space See also D region, E region, F region
Derived Forms
ionospheric (aɪˌɒnəˈsfɛrɪk) adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for ionospheric

ionosphere

n.

1926, from ion + sphere. Coined by Scottish radar pioneer Robert A. Watson-Watt (1892-1973). So called because it contains many ions.

Online Etymology Dictionary, © 2010 Douglas Harper
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ionospheric in Science
ionosphere
  (ī-ŏn'ə-sfîr')   
A region of the Earth's upper atmosphere, extending from a height of 70 km (43 mi) to 400 km (248 mi) and containing atoms that have been ionized by radiation from the Sun. The ionosphere lies mostly in the lower thermosphere and is subdivided into three regions, the D region (70 km to 90 km; 43 to 56 mi), the E region (90 km to 150 km; 56 to 93 mi), and the F region (150 km to 400 km; 93 to 248 mi). The concentration of ionized atoms is lowest in the D region, intermediate in the E region, and highest in the F region. The ionosphere is useful for radio transmission because radio waves, which normally propagate in straight lines, are reflected off the ionized gas particles, thereby being transmitted long distances across the Earth's curved surface. See more at D region, E region, F region.

The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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ionospheric in Culture
ionosphere [(eye-on-uh-sfeer)]

A region of the atmosphere that begins at an altitude of about thirty miles.

Note: In this region, free particles carrying an electrical charge, atoms ionized (see ionization) by radiation from the sun, reflect radio waves. “Bouncing” radio waves off the ionosphere makes communication possible over long distances of the surface of the Earth.
The American Heritage® New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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