Word Study
d-layer
WORDNET DICTIONARY
Noun d-layer has 1 sense
- d-layer(n = noun.location) d region - the lowest region of the ionosphere (35 to 50 miles up) that reflects low-frequency radio waves; Array is a part of ionosphere
is a kind of part, region
OXFORD DICTIONARY
d-layer, n. the lowest layer of the ionosphere able to reflect low-frequency radio waves.
Etymology
D (arbitrary)
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