line of apsides

American  

noun

Astronomy.

1. the major axis of an elliptical orbit.

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Example Sentences

The time of revolution of a primary or secondary planet in reference to its line of apsides; that is, from one perigee or apogee to another.

From The Sailor's Word-Book An Alphabetical Digest of Nautical Terms, including Some More Especially Military and Scientific, but Useful to Seamen; as well as Archaisms of Early Voyagers, etc. by Belcher, Edward, Sir

That is to say, he assumed a revolving line of apsides in an elliptical orbit traversed by a pretty strongly compressed pair of globes.

From A Popular History of Astronomy During the Nineteenth Century Fourth Edition by Clerke, Agnes M. (Agnes Mary)

The more distant is called the higher apsis; the other, the lower apsis; and the line joining them, the line of apsides.

From Webster's Unabridged Dictionary by Webster, Noah

Change of line of apsides; period about 21,000 years.

From Astronomical Curiosities Facts and Fallacies by Gore, J. Ellard