duplication (n.)youdaoicibaDictYouDict[duplication 词源字典]
early 15c., "doubling," from Middle French duplicacion (13c.) and directly from Latin duplicationem (nominative duplicatio), noun of action from past participle stem of duplicare (see duplicate (adj.)). Meaning "repetition" is from 1580s.[duplication etymology, duplication origin, 英语词源]