d region

1. 1.

   the lowest region of the ionosphere (35 to 50 miles up) that reflects low-frequency radio waves

   SynonymsD-layer

   Broaderregion

   Part ofionosphere

Questions about d region

What does d region mean?

d region means "the lowest region of the ionosphere (35 to 50 miles up) that reflects low-frequency radio waves".

What is another word for d region?

Close synonyms include D-layer. Each sense on this page lists its own synonyms, because a word with several meanings rarely has one substitute that works for all of them.

Is d region a common word?

d region is banded "Uncommon" — turns up in careful writing rather than conversation. The band comes from how often the word appears in a large corpus of everyday English, not from an editor's impression.