semi·​di·​am·​e·​ter ˌse-mē-dī-ˈa-mə-tər How to pronounce semidiameter (audio)
: 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

Cite this Entry

“Semidiameter.” Dictionary, Merriam-Webster, Accessed 18 May. 2024.

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