oscillate (v.)youdaoicibaDictYouDict[oscillate 词源字典]
1726, back-formation from oscillation, or else from Latin oscillatus, past participle of oscillare (see oscillation). From 1917 in electronics. Related: Oscillated; oscillating.[oscillate etymology, oscillate origin, 英语词源]
librationyoudaoicibaDictYouDict
"An apparent or real oscillation of the moon, by which parts near the edge of the disc that are often not visible from the earth sometimes come into view", Early 17th century (denoting an oscillating motion, or equilibrium): from Latin libratio(n-), from the verb librare, from libra 'a balance'.