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English definition of “the ionosphere”

the ionosphere

noun [S]     /aɪˈɒn.əˌsfɪər/ US  /-ˈɑːn.əˌsfɪr/ specialized
part of the Earth's atmosphere, from about 60 kilometres to about 1,000 kilometres above the surface, in which there are many ions → Compare the exosphere, the mesosphere, the stratosphere, the thermosphere, the troposphereThe Earth and outer space - general words ionospheric     /aɪˌɒ.nəˈsfer.ɪk/ US  /-ˌɑːn.ə-/ adjective The Earth and outer space - general words
(Definition of the ionosphere noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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