noun li·bra·tion \lī-ˈbrā-shən\

Definition of libration

  1. :  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


play \lī-ˈbrā-shnəl, -shə-nəl\ adjective


play \ˈlī-brə-ˌtȯr-ē\ adjective

Origin and Etymology of libration

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

First Known Use: 1667

Learn More about libration

Seen and Heard

What made you want to look up libration? Please tell us where you read or heard it (including the quote, if possible).