F region

noun

: the highest region of the ionosphere occurring from 80 miles (130 kilometers) to more than 300 miles (500 kilometers)

Word History

First Known Use

1923, in the meaning defined above

Time Traveler
The first known use of F region was in 1923

Dictionary Entries Near F region

Fregean

F region

freibergite

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Cite this Entry

“F region.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/F%20region. Accessed 21 Nov. 2024.

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Britannica.com: Encyclopedia article about F region

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