lever (n.)youdaoicibaDictYouDict[lever 词源字典]
c. 1300, from Old French levier (Modern French leveur) "a lifter, a lever," agent noun from lever "to raise," from Latin levare "to raise," from levis "light" in weight, from PIE root *legwh- "light, having little weight; easy, agile, nimble" (cognates: Sanskrit laghuh "quick, small;" Greek elakhys "small," elaphros "light;" Old Church Slavonic liguku, Lithuanian lengvas "light;" Old Irish laigiu "smaller, worse;" Gothic leihts, Old English leoht "light" (adj.)). As a verb, 1856, from the noun.[lever etymology, lever origin, 英语词源]