F layer

[ ef-ley-er ]
/ ˈɛf ˌleɪ ər /
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noun Physics.
the highest of the radio-reflective layers of the ionosphere, beginning at an altitude of about 80 miles (130 km) and consisting of two parts, the lower part (F1 layer ) being detectable in the daytime only, the higher (F2 layer, or Appleton layer ) being constant and constituting the ionospheric layer most favorable for long-range radio communication.
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Origin of F layer

First recorded in 1925–30

Words nearby F layer

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use F layer in a sentence

Scientific definitions for F layer

F layer

See F region.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.