libratory

American  

[lahy-bruh-tawr-ee, -tohr-ee] / ˈlaɪ brəˌtɔr i, -ˌtoʊr i /

adjective

1. oscillatory.

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Etymology

Origin of libratory

First recorded in 1660–70; librate + -ory ¹

Example Sentences

The Evection, an irregular motion of the Moon discovered by Ptolemy, whereby her mean longitude is increased or diminished, was explained by Horrox as depending upon the libratory motion of the apsides, and the change which takes place in the eccentricity of the lunar orbit.

From Project Gutenberg

Moreover, since her orbit is nearly circular, libratory effects are very small.

From Project Gutenberg

Herschel had a theory on the subject—viz., that just where the balancing or libratory swing of the moon brings into view the greatest extent beyond the eastern or western parts of that hemisphere which is turned earthwards in the moon's mean or average position, lunar inhabitants would probably be found, and nowhere else.

From Project Gutenberg

Another effect of the libratory motion of the sun as seen from Mercury is represented in the next figure, where we have a view of the planet showing both the day and the night hemisphere, and where we see that between the two there is a region upon which the sun rises and sets once every eighty-eight days.

From Project Gutenberg

As was remarked a little while ago, the moon traveling in an elliptical orbit about the earth has a libratory movement which, if represented in our picture, would cause the cross to swing now a little one way and now a little the other, and thus produce an apparent pendulum motion of the earth in the sky, similar to that of the sun as seen from Mercury.

From Project Gutenberg