D region


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D region

n.

D region

or

D layer

n
(General Physics) the lowest region of the ionosphere, extending from a height of about 60 kilometres to about 90 kilometres: contains a low concentration of free electrons and reflects low-frequency radio waves. See also ionosphere

D layer


n.
the lowest region of the ionosphere, at an altitude of ab. 50 mi. (80 km).
[1930–35]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.D region - the lowest region of the ionosphere (35 to 50 miles up) that reflects low-frequency radio waves
ionosphere - the outer region of the Earth's atmosphere; contains a high concentration of free electrons
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