centenary (adj.)youdaoicibaDictYouDict[centenary 词源字典]
c. 1600, "period of 100 years," from Latin centenarius "of a hundred, relating to a hundred," from centenai "a hundred each," from centum "hundred" (see hundred). As a noun, "100th anniversary," from 1788.[centenary etymology, centenary origin, 英语词源]