li·bra·tion  (lī-brā'shən)  n. A very slow oscillation, real or apparent, of a satellite as viewed from the larger celestial body around which it revolves. [Latin lībrātio, lībrātiōn-, oscillation, from lībrātus, past participle of lībrāre, to balance, from lībra, balance.] li·bra'tion·al adj., li'bra·to'ry (-brə-tôr'ē, -tōr'ē) adj. |
brəˌtɔr