semimajor axis

noun

semi·​ma·​jor axis ˌse-mē-ˈmā-jər- How to pronounce semimajor axis (audio)
ˌse-ˌmī-,
-mi-
: one half of the major axis of an ellipse (such as that formed by the orbit of a planet)

Examples of semimajor axis in a Sentence

Recent Examples on the Web
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
The uncertainty in its semimajor axis (the radius of its orbit at its two most separated points) is just six meters out of a total length of 168,505,699.049 kilometers. Dante S. Lauretta, Scientific American, 1 Aug. 2016

Word History

First Known Use

1818, in the meaning defined above

Time Traveler
The first known use of semimajor axis was in 1818

Dictionary Entries Near semimajor axis

Cite this Entry

“Semimajor axis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/semimajor%20axis. Accessed 16 Nov. 2024.

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