ionosphere

[ ahy-on-uh-sfeer ]

/ aɪˈɒn əˌsfɪər /

noun

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.

Nearby words

ionone, ionopause, ionophore, ionophoresis, ionosonde, ionosphere, ionospheric wave, ionotropic receptor, ionotropy, iontophoresis, ioof

Origin of ionosphere

First recorded in 1925–30; iono- + -sphere

Related forms

i·on·o·spher·ic

[ahy-on-uh-sfer-ik] /aɪˌɒn əˈsfɛr ɪk/, adjective

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for ionosphere

They struck the Earth's ionosphere, and their numbers diminished.
Out Like a Light|Gordon Randall Garrett
The ionosphere of Eisberg was much deeper and, although the intensity was less, the duration was much longer.
Unwise Child|Gordon Randall Garrett
Extensive reports on the condition 176 of the ionosphere poured into headquarters.
Tom Swift and The Visitor from Planet X|Victor Appleton
Without the landing grid and the power it took from the ionosphere, they could not receive supplies from the rest of the universe.
Sand Doom|William Fitzgerald Jenkins

Then we were able to modify that to heave sand and to let it tap the ionosphere.
Sand Doom|William Fitzgerald Jenkins

British Dictionary definitions for ionosphere

ionosphere

/ (aɪˈɒnəˌsfɪə) /

noun

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 spaceSee 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

Science definitions for ionosphere

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.

Culture definitions for ionosphere

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.