libration

noun li·bra·tion \lī-ˈbrā-shən\

Definition of LIBRATION

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

— li·bra·tion·al \-shnəl, -shə-n^əl\ adjective

— li·bra·to·ry \ˈlī-brə-ˌtȯr-ē\ adjective

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

First Known Use: 1667

Next Word in the Dictionary: libration of the moonPrevious Word in the Dictionary: librate All Words Near: libration

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