major axis


: the axis passing through the foci of an ellipse

Examples of major axis in a Sentence

Recent Examples on the Web The Earth orbits the Sun in an ellipse that is pretty close to being a perfect circle, and by definition the semi-major axis of our orbit is 1.0. Phil Plait, Discover Magazine, 26 June 2011 The orbit is more elliptical than Earth's, with a semi-major axis of 1.056 AU. Phil Plait, Discover Magazine, 26 June 2011 Technically, an Aten asteroid has a semi-major axis less than one Astronomical Unit. Phil Plait, Discover Magazine, 26 Sep. 2012 Orbits are elliptical, and the semi-major axis is the half-diameter of the orbit along the long axis. Phil Plait, Discover Magazine, 26 Sep. 2012

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'major axis.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1879, in the meaning defined above

Time Traveler
The first known use of major axis was in 1879

Dictionary Entries Near major axis

Cite this Entry

“Major axis.” Dictionary, Merriam-Webster, Accessed 23 Apr. 2024.

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