semidiameter

noun

semi·​di·​am·​e·​ter ˌse-mē-dī-ˈa-mə-tər How to pronounce semidiameter (audio)
ˌse-ˌmī-,
-mi-
: radius
specifically : the apparent radius of a generally spherical celestial body

Word History

First Known Use

14th century, in the meaning defined above

Time Traveler
The first known use of semidiameter was in the 14th century

Dictionary Entries Near semidiameter

semidetached

semidiameter

semidiesel engine

See More Nearby Entries 

Cite this Entry

“Semidiameter.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/semidiameter. Accessed 22 Nov. 2024.

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