li·​bra·​tion | \ lī-ˈbrā-shən How to pronounce libration (audio) \

Definition of libration

: an oscillation in the apparent aspect of a secondary body (such as a planet or a satellite) as seen from the primary object around which it revolves

Other Words from libration

librational \ lī-​ˈbrā-​shnəl How to pronounce libration (audio) , -​shə-​nᵊl \ adjective
libratory \ ˈlī-​brə-​ˌtȯr-​ē How to pronounce libration (audio) \ adjective

Examples of libration in a Sentence

Recent Examples on the Web The discovery pivots on the detection of a curious libration—a wobble—in the rotation of Mimas. Jamie Carter, Forbes, 19 Jan. 2022

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'libration.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of libration

1667, in the meaning defined above

History and Etymology for libration

Latin libration-, libratio, from librare to balance, from libra scales

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Time Traveler for libration

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The first known use of libration was in 1667

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Dictionary Entries Near libration



libration of the moon

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Cite this Entry

“Libration.” Dictionary, Merriam-Webster, Accessed 6 Jul. 2022.

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